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Dorrell, Robert Michael. "Particulate Suspensions : The Mechanics of Suspension and Deposition." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525454.
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Carpen, Ileana Cristina Brady John F. Brady John F. "Studies of suspension behavior : I. Instabilities of non-Brownian suspensions. II. Microrheology of colloidal suspensions /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-06022005-131439.
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Lam, Duhane. "Bicycle suspension design." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0025/MQ51383.pdf.
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Jenkins, Chadlea. "Vehicle suspension design." Thesis, University of Salford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395699.
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Junior, Luís Mauro Pereira Freitas. "Estudo da dinâmica vertical de uma suspensão veicular do tipo MacPherson." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-19012011-114031/.
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O sistema de suspensão de um veículo desempenha papel fundamental na isolação das vibrações provenientes da pista e de outras fontes de excitações e tem como alguns de seus objetivos: melhoria do conforto dos passageiros, manutenção da integridade das cargas e das vias (asfalto), aumento da segurança, proporcionando melhores condições de aderência pneu-piso, etc. A predição do desempenho de um sistema de suspensão veicular antes da construção de um protótipo físico, permite o dimensionamento prévio dos componentes que o integram com maior precisão, otimizando-se, desta forma, o custo final do produto bem como custos e prazos decorrentes de modificações para solucionar problemas que seriam detectados somente na experimentação do protótipo físico. Este trabalho apresenta um comparativo entre os resultados analíticos obtidos utilizando-se as funções transferências de um modelo simplificado (ou clássico) linear de uma suspensão automotiva de 1/4 de veículo (quarter-car); dos obtidos através da utilização de um protótipo virtual do mesmo modelo simplificado (ou clássico) de 1/4 de veículo e, por fim, dos obtidos utilizando-se um protótipo virtual de um sistema de suspensão do tipo MacPherson, sendo que os protótipos virtuais podem trabalhar com não-linearidades. São obtidas as respostas dinâmicas no domínio da frequência (0 a 30 Hz) e também no domínio do tempo, neste último caso utilizando-se como entrada um pulso no pneu, que simula a passagem do veículo sobre um obstáculo a 18 Km/h. Os resultados são comparados objetivamente e conclui-se sobre as limitações de utilização do modelo simplificado (ou clássico) de 1/4 de veículo.The performance of the suspension system of a vehicle is fundamental to isolate the vibrations from road and from other sources and has the following objetives: improve the comfort of passengers (ride), protect the cargo and the road (asphalt), improve vehicle handling, etc. The prediction of the performance of a vehicle´s suspension system prior to the real prototype construction, allows the previous optimization of the design of the suspension´s components, obtaining a low cost product, in a shorter timming, with lower development costs, by solving problems that would be evident only during the tests with the real prototype. This study presents a comparison between analitycal results obtained by the use of transfers functions of a plain or classical linear model of a automotive suspension system named quarter-car; the results obtained from a virtual prototype of the same plain or classical model and, finally, the results obtained from a virtual prototype of a Macpherson suspension system, considering that the virtuals prototypes are be able to work with non-linearities. The dynamic response are obtained in the frequency domain (0 a 30 Hz) and in the time domain too, in this last case, with a pulse input in the tire, that simulates the car passing over a bump with a speed of 18 Km/h. Through the comparison of the results is possible to conclude about the limitations of the classical model.
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Schlicker, Bruce M. "Composite suspension member analysis." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4818.
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Thesis (M.S.)--West Virginia University, 2006.Title from document title page. Document formatted into pages; contains ix, 78 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 74-75).
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Paterson, Colin Alexander. "Computer controlled suspension systems." Thesis, Coventry University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357047.
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Zhang, Yantong, and Pedro Escribano. "Active Forwarder Cab Suspension." Thesis, KTH, Maskinkonstruktion (Inst.), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190138.
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The forest industry plays an important role in Sweden, and forest machine manufactures are underconstant pressure to achieve both high productivity and comfortable operating environment in its products. A forwarder is a forestry vehicle that carries logs which are cut by a harvester. It suffers alot of low frequency and high amplitude vibrations during the operation because of the rough terrainin forests. Therefore, it is necessary and vital to introduce an active cab suspension system in orderto reduce the whole vibrations in the forwarder cab.The main purposes of this thesis are to develop, implement and test a feasible control strategy forthe active cab suspension system as well as verify the controller’s performance in terms of vibrationreduction and power consumption. This project is focused on the available mechanical rig installedat KTH lab hall, instead of a real forwarder.A deep study has been carried out on a new valve prototype. Exhausted tests were made to testthe performance of this valve under different conditions. From the test results, the valve was tunedin order to get the best performance out of it. Once the valve has been well calibrated, a model ofthe whole system was estimated by using Black-box estimation. The model has a 96% of matchingbetween the stimulation data and the validation data. Different controllers were designed with thismodel, and the best one was designed by the gain scheduling method.The system has a delay of 36 ms, therefore, it was studied how the performance of this controllerwould increase if this delay was reduced. The study shows that reducing the delay to around 0-2ms, the suspension system is able to reduce the vibration from 60% to 90%. Smith Predictor wasimplemented into the gain scheduling controller in order to reduce the effect of the delay. The resultsdemonstrated a better and more robust performance of the controller with Smith Predictor.Several test cases were implemented to seek a wide range of possible vibrations that a forwardercould handle in the forest. These tests have been done both in a test rig and in a simulationenvironment. The final test was conducted by using a real track test model obtained from Skogforsk.This track is used for testing different systems in a test forwarder since it simulates the terrain ina forest. Based on the simulation result, the total disturbance reduction percentages of SmithPredictor controller are 75% for heave, 68% for pitch and 73% for roll, which shows the systemreduces the cab vibration. Moreover, the maximum amount of power needed during the forwarderoperation is 11.63 kW which is feasible for implementing this system on the actual forwarder.
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Rocha, Caio Cesar Vieria. "The "Action of Suspension"." Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=4002.
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O trabalho ora apresentado pretendeu investigar o instituto do pedido de suspensÃo à luz dos princÃpios constitucionais do processo, analisando sua constitucionalidade material e formal. Situamos o referido instituto no tempo e espaÃo, atravÃs de anÃlise histÃrica e comparando-o com similares de outros paÃses. Em seguida, justificamo-lo no princÃpio da supremacia do interesse pÃblico sobre o privado, demonstrando que sua criaÃÃo decorreu da aplicaÃÃo do princÃpio da proporcionalidade utilizado pelo legislador para resolver o aparente embate entre aquele e o princÃpio do acesso à justiÃa. Para demonstrar a sua constitucionalidade material, cotejamo-lo com os mais importantes princÃpios processuais, alÃm de apontar a inconstitucionalidade formal da medida provisÃria que o regulamenta. Demonstramos sua validade legal perante as normas processuais infraconstitucionais. Analisamos a sua natureza jurÃdica, a fim de melhor conceituÃ-lo no ordenamento. Por fim, dedicamo-nos a discorrer sobre o seu processamento, concluindo, em especÃfico, que para harmonizar-se com o ordenamento constitucional, a sua anÃlise deve ser precedida de um mÃnimo juÃzo de delibaÃÃo da causa principal, em que o princÃpio da proporcionalidade deve ser utilizado para averiguar a probabilidade de modificaÃÃo da decisÃo objeto do pedido de suspensÃo, em face da gravidade da lesÃo que se apresenta.The presented work intended to investigate the institute of the âAction of Suspensionâ (âPedido de SuspensÃoâ), by the light of the most important constitutional principles, analyzing its material and formal constitutionality. We point out the cited institute in time and space, through historical analysis and comparison to its similars from other countries. After that, we justified it in the principle of the supremacy of the public above private interest, demonstrating that its creation elapsed from the application of the proportionality principle used by the legislator to solve the apparent conflict between the shock of the supremacy of the public interest and the access to justice. To demonstrate its material constitutionality, we analysed it with the most important procedural principles, and pointed out the formal unconstitutionality of the provisional remedy that regulates it. We demonstrate its legal validity before the procedural infraconstitutional norms. We analyzed its legal nature, in order to better appraise it in the legal system. At last, we spent some time discoursing on its processing, concluding, in specific, that to harmonize itself with the constitutional order, its analysis must be preceded by a minimum judgment of the litigation cause, where the proportionality principle must be used to inquire the probability of future modification of the decision subject-matter of the action of suspension, in face of the gravity of the injury that if presents.
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Day, Jason J. "Topologically Mixing Suspension Flows." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8389.
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We find a set of conditions on a roof function to ensure topological mixing for suspension flows over a topological mixing base. In the measure theoretic case, such conditions have already been established for certain flows. Specifically, certain suspensions are topologically mixing if and only if the roof function is not cohomologous to a constant. We show that an analogous statement holds to establish topological mixing with the presence of dense periodic points. Much of the work required is to find properties specific to the equivalence class of functions cohomologous to a constant. In addition to these conditions, we show that the set of roof functions that induce a topologically mixing suspension is open and dense in the space of continuous roof functions.
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Sjöstrand, Philip. "New bogie suspension concept." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-76947.
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There is always a desire to develop and offer the best and most protable products on the market. This master thesis in mechanical engineering investigates the possibility to reduce the costs of the bogie suspension on Volvo's articulated haulers. The so called stays in the existing bogie suspension are significant components that connects the axle housings to the frame. The existing solution consists of stays that are expensive, heavy and time consuming to manufacture. Concepts in CAD will be compared to each other and and all concept will be evaluated in more detail. Totally five concepts were generated and modelled. They were compared regarding strains on rubber parts, required stay dimensions, collision between different parts and axle movements. Two proceeded concepts for further development after the evaluation and two new concepts were generated. A new comparison was made with additional tests. Simulations conrmed that it was only possible to proceed with one of the two developed concepts because one of the concepts would require large dimensions to manage the applied forces. The selected concept was redesigned and adapted to be as realizable as possible. Bushing kits, reinforcements, and detailed designs of parts were considered. Simple FEMcalculations was only made on parts that wasn't depending on components on the frame since these calculations would be too advanced and time consuming. The resulting concept needs more work to be realizable since there are geometry optimization on molded components left as well as advanced calculations when integrating the solution on the frame. A weight loss ofapproximately 95kg and a cost reduction of 3700SEK was made. Further investigations has to be done to determine if it's possible to obtain a positive business case with the new bogie suspension.
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Sarami, Shahriar. "Development and evaluation of a semi-active suspension system for full suspension tractors." Berlin TU, Fachbereich Konstruktion von Maschinensystemen, 2009. http://d-nb.info/1000917142/34.
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Van, der Westhuizen Sarel Francois. "Slow active suspension control for rollover prevention." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/25432.
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Rollover prevention in Sports Utility Vehicles (SUV‟s) offers a great challenge in vehicle safety. By reducing the body roll angle of the vehicle the load transfer will increase and thus decrease the lateral force that can be generated by the tires. This decrease in the lateral force can cause the vehicle to slide rather than to roll over. This study presents the possibility of using slow active suspension control to reduce the body roll and thus reduce the rollover propensity of a vehicle fitted with a hydro-pneumatic suspension system. The slow active control is obtained by pumping oil into and draining oil out of each hydro-pneumatic suspension unit individually. A real gas model for the suspension units as well as for the accumulator that supplies the oil is incorporated in a validated full vehicle Adams model. This model is then used to simulate a double lane change manoeuvre performed by a SUV at 60 km/h and it is shown that a significant improvement in body roll can be obtained with relatively low energy requirements. The proposed control is successfully implemented on a Land Rover Defender test vehicle. A Proportional-Derivative (PD) controller is used to control on-off solenoid operated valves and the flow is adjusted using the lateral acceleration as a parameter. Experimental results confirm that a significant improvement in body roll is possible. AFRIKAANS : Omrolvoorkoming in Sportnutsvoertuie bied geweldige uitdagings in terme van voertuigveiligheid. Deur die rolhoek van die voertuig te verminder word die laterale lasoordrag verhoog en word die laterale krag wat die bande kan genereer minder. As die laterale krag genoeg verminder sal die voertuig eerder gly as omrol. Die studie ondersoek die moontlikheid om stadig-aktiewe suspensiebeheer op 'n voertuig met 'n hidropneumatiese suspensie te gebruik om bakrol te verminder en dus die omrolgeneigdheid van die voertuig te verlaag. Die beheer word toegepas deur olie in elke hidropneumaties suspensie-eenheid individueel in te pomp of te dreineer. 'n Werklike gas model word gebruik om die supensie-eenhede asook die akkumulator, wat die olie aan die suspensie voorsien, te modeleer. Hierdie modelle word in 'n gevalideerde volvoertuig ADAMS model geïnkorporeer en 'n dubbel laanverwisseling word gesimuleer teen 60 km/h. Die resultate toon dat 'n beduidende verbetering in die rolhoek moontlik is met relatiewe lae energievereistes. Die voorgestelde beheer is suksesvol op 'n Land Rover Defender geïmplimenteer en 'n Proportioneele-Differensiaal (PD) beheerder word gebruik om die aan-af solenoїde kleppe te beheer terwyl die vloei aangepas word na gelang van die laterale versnelling. Eksperimentele resultate bevestig dat 'n beduidende verbetering in bakrol moontlik is.Dissertation (MEng)--University of Pretoria, 2012.
Mechanical and Aeronautical Engineering
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Karlqvist, Rasmus. "Hydropneumatic suspension in a truck : Installation of a hydropneumatic suspension for a Scania truck." Thesis, Karlstads universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78647.
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Investigation and testing of hydropneumatic suspension systems has previously been done at Scania between the year 1992 and 2000. Interest has aroused at Scania CV AB to further test a hydropneumatic suspension. The reason being the new ventures of decarbonised, clean, electrified, automatized and digitalised vehicles. If electrified trucks are to be adopted in the market as an alternative to trucks with combustion engines, solutions for this type of vehicle’s capacity need to be presented. The vehicle’s weight needs to be reduced; the effectiveness of the components needs to be increased and alternatives to increase battery storage needs to arise if it’s going match the traveling distance of a combustion engine. The mission of the project is to present an installation solution of a hydropneumatic suspension that retains the performance of the current air suspension. The presented material will contain CAD-models of all the brackets that will be designed to fit the suspension, as well as the placement in the vehicle assembly for said brackets. The results show that as for the front suspension the best solution is a placement of the hydraulic cylinders in front of the vehicles front axle. Furthermore the rear suspension is best suited for a placement of the hydraulic cylinders behind the vehicles rear axle. However it was concluded that the rear suspension will not be able to retain the current stroke of the vehicle without sacrificing its ground clearance. Parts of the suspension could however be terminated when the air suspension system was replaced by the hydropneumatic system namely: The front suspension anti-roll bar, shock absorbers, air springs and their coexisting brackets.
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Injety, Sahana. "Formulation of a nevirapine co-crystal as a liquid dosage form." University of the Western Cape, 2016. http://hdl.handle.net/11394/5060.
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Magister Pharmaceuticae - MPharmCo-crystals are a solid phase phenomena that could enhance the physicochemical properties of an active pharmaceutical ingredient. A co-crystal has never been incorporated into a liquid dosage form with the assurance of maintaining its co-crystal state until absorption under defined conditions. This study aims to develop a liquid formulation with a nevirapine co-crystal. A protocol was developed to investigate all the five co-formers that were used to make the nevirapine co-crystals to-date. The most appropriate co-former was selected for a liquid dosage form to study the integrity and the scaling up of the co-crystal in a suspension formulation. Co-formers used were viz. saccharin, glutaric acid, salicylic acid, rac-tartaric acid and maleic acid. These were characterized according to their physical, chemical, pharmacological and pharmaceutical properties. A grading scale was used to select the most appropriate co-former for a suspension formulation. Comparatively, saccharin produced the best combination of physical, chemical, pharmacological and pharmaceutical properties, especially with regard to the particle size and the specific gravity which proved to be very useful as optimal criteria for suspension formulation. Upon selection of the ideal co-former, scale-up of the nevirapine saccharin co-crystal was performed from a small scale of 350 mg to a large scale of 5 g. Nevirapine-saccharin (NVSC) co-crystals were prepared utilizing the slow evaporation technique, using methanol as the solvent and the percentage yield of the co-crystals were > 80 %. The identity of co-crystals was confirmed using hot stage microscopy (HSM), differential scanning calorimetry (DSC), fourier transform infra- red (FTIR) and thermogravimetric analysis (TGA). Three co-crystal suspension formulations were prepared using the excipients identified in the branded, Viramune® suspension, with each formulation containing viscosity enhancers such as aerosil 200, carbopol 971G and carbopol 974P. To ascertain the co- crystal integrity in the suspension, it was filtered and the filtrate was identified with DSC and FTIR while the filtered solution was identified with ultraviolet spectroscopy (UV). The co-crystal suspension formulation with optimal pH, viscosity and assurance of co-crystal integrity was the carbopol 974P formulation. The UV and DSC of the filtrate of the suspension revealed that the co-crystal had not separated into its individual components and remained intact while in suspension form irrespective of the excipients added. This formulation proceeded to the quality control stage. It was assessed for its pH, viscosity and dissolution according to the USP 32 standards and compared to the branded nevirapine suspension, Viramune ®, presently on the market. The suspension was characterized for particle size, zeta potential and polydispersity index. The dissolution results assayed by High Performance Liquid Chromatography (HPLC) revealed a drug release of 86 % in the Viramune® suspension while the NVSC co- crystal suspension achieved a drug release of 94% within 30 minutes of dissolution.
National Research Foundation (NRF)
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Wolfe, Sage. "SLASIM a suspension analysis program /." Connect to resource, 2010. http://hdl.handle.net/1811/45363.
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Grigor, Charles Miller. "Suspension in the disciplinary process." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020966.
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Employers often wrestle with whether or not to suspend an employee and the issue is what needs to be done before an employee could be suspended. Suspending an employee means to deprive him or her from entering the work place for a period of time, due to alleged misconduct which, due to the nature of the alleged misconduct and in the opinion of the employer, warrants the employee not to be in or near the workplace. Section 23 of the Constitution of the Republic of South Africa, affords every employee the right to fair labour practices and this right should be affected by the Labour Relations Act, 1995 (LRA). Unfortunately the LRA only deals with the unfair suspension under the definition of an unfair labour practice in section 186(2) by stating that the meaning of unfair labour practice is any act or omission that arises between an employer and an employee involving the unfair suspension of an employee or any other unfair disciplinary action short of dismissal in respect of an employee. The focus of this document thus is to scrutinise the lack of legislative guidelines relating to the procedural fairness of suspension of employees. It would thus necessitate an overview of the nature of suspension which would be discussed in length by way of referring to the right to suspend an employee as well as the application of the courts in such cases, the distinction between suspension as a preventative, or as a punitive measure and the possibility of suspension resulting in an unfair labour practice. The distinction between preventative and punitive suspensions are highlighted. Since it is not clear when, how and for how long an employee may be suspended, in the absence of clear guidelines, employers have to turn to the courts’ interpretation to get the necessary guidance on the application of a suspension. In order to ensure that the employer, experiencing unnecessary difficulty with the implementation of procedural fairness of suspensions, in a meaningful way, be assisted by the proposal that legislature consider to address this by including clear guidelines under Item 3 of Schedule 8 of the LRA.
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Xu, Zhiming. "Sediment suspension under groupy waves." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0012/NQ33921.pdf.
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Usher, Shane Patrick. "Suspension dewatering : characterisation and optimisation /." Connect to thesis, 2002. http://eprints.unimelb.edu.au/archive/00000972.
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翁若愚 and Yeuk-yu Yung. "Suspension of judgement: Agrippa andepoche." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B42576568.
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Bayer, Emmanuelle M. "Plasmodesmata in Arabidopsis suspension cells." Thesis, University of East Anglia, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423814.
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SILVA, LUIS DIEGO VALDEZ. "SLOT COATING OF PARTICLE SUSPENSION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=23831@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
PROGRAMA DE EXCELENCIA ACADEMICA
O processo de revestimento por extrusão é muito usado na fabricação de produtos de alta tecnologia tais como circuitos flexíveis, telas LCD e OLED, dentre outros. A espessura do filme revestido depende da vazão de alimentação e da velocidade do substrato. O estudo do escoamento na região de aplicação é de muita importância, devido à influência que tem sobre a qualidade do filme revestido. A grande maioria dos trabalhos disponíveis na literatura consideram o líquido como um fluido Newtoniano. Porém, nos processos de revestimentos nas indústrias, os líquidos comumente usados são soluções poliméricas e suspensões de partículas. O efeito da presença de moléculas poliméricas dissolvidas no fluido de trabalho nos padrões de escoamento e consequentemente na janela de operação do processo foi estudado recentemente, contudo, o efeito de partículas suspensas no escoamento é ainda desconhecido. O objetivo deste trabalho é compreender melhor a influência da suspensão de partículas no padrão de escoamento que ocorre na região de aplicação de um filme fino de líquido sobre um substrato em movimento. A variação local da concentração de partículas no líquido pode levar a grande variações na viscosidade e consequentemente mudanças no escoamento e nos limites do processo. Neste estudo, considera-se a suspensão como um sistema formado por um fluido Newtoniano como a fase contínua e partículas esféricas rígidas como a fase dispersa. A equação de transporte de partículas engloba os efeitos de difusão de partículas devido a gradientes de concentração, viscosidade e taxa de deformação. As equações de transporte de partículas em conjunto com as equações de conservação de massa e quantidade de movimento são usadas para descrever o escoamento bidimensional com fronteiras livres. Estas equações são resolvidas aproximadamente pelo método de Galerkin/Elementos Finitos. A validação do código numérico foi feita comparando com resultados analíticos disponíveis para escoamento em tubos de seção circular. Os resultados obtidos para o escoamento no precesso de revestimento por extrusão mostram as regiões de maior e menor concentração de partículas e como esta variação altera o escoamento, e a variação da concentração ao longo da espessura do filme depositado.
Slot coating process is commonly used in the manufacture of high technology products such as flexible circuits, LCD and OLED displays, among others. The thickness of the coated liquid film depends on the flow rate and substrate velocity. It is very important to study the flow in the coating bead region, because the flow pattern has a strong effect on the quality of the coated film. Most of the available studies on slot coating consider the fluid as a Newtonian liquid. However, coating liquids are usually polymer solutions or particle suspensions. The effect of dissolved polymer molecules in the flow has been analyzed recently. However, the effect of suspended particle remains unknown. The goal of this work is to develop a fundamental understanding of the effect of suspended particles in the flow pattern in a slot coating process. The local changes in particle concentration can lead to great changes in the local liquid viscosity and consequently in the flow and process limits. In this research, the particle suspension is a system composed by a Newtonian liquid as a continuous phase and rigid spherical particles as the dispersed phase. The particle transport equations takes into account the diffusion due to gradients of concentration, viscosity and deformation rates. The particle transport equation together with the mass and momentum conservation equations are used to describe the two-dimensional free surface flow. These equations are solved using the Galerkin/Finite element method. The numerical code was validated by comparing numerical prediction obtained in circular tube flow with the available exact solution. The results obtained in slot coating flow show regions of high and low concentration of particles and its effect of the flow, and the variation of particle concentration in the deposited thin film.
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ARAUJO, SIMONE BOCHNER DE. "SLOT COATING OF PARTICLE SUSPENSION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=24640@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOO processo de revestimento por extrusão é um método muito utilizado na manufatura de diversos produtos. Ele pertence à uma classe de processos de revestimento chamada revestimento com vazão pré-fixada: para operações em regime permanente, a espessura da camada de líquido revestida é definida pela vazão na entrada do equipamento e pela velocidade do substrato. Para diversas aplicações, o líquido de revestimento é uma suspensão de partículas. A abordagem comumente usada é analisar o escoamento como se o fluido fosse Newtoniano, onde sua viscosidade é avaliada pela concentração média de partículas. Porém, dados experimentais mostram que a distribuição de partículas não é uniforme em escoamentos com cisalhamento. Além disso, a distribuição de partículas no filme após o processo de revestimento afetará a estrutura final do filme e, consequentemente, a qualidade final do produto. Portanto, é importante entender os fundamentos do processo de revestimento com suspensão de partículas para melhor descrever este processo e prever comportamentos desse escoamento. O objetivo do presente trabalho é estudar diferentes mecanismos de migração de partículas em suspensão que podem afetar a distribuição de partículas no filme revestido; como mecanismos de difusão e sedimentação. O modelo apresentado leva em consideração a dependência da viscosidade pela concentração local de partículas e o efeito de Marangoni. Dois modelos diferentes foram usados para estudar o escoamento de Marangoni. No primeiro, o transporte de partículas entre a superfície e o escoamento é considerado muito mais rápido que a difusão no escoamento de tal forma que o fluxo líquido é zero e a concentração de partículas na região do escoamento próxima à superfície. No segundo, um modelo mais completo, os efeitos de adsorção e dessorção de partículas pela interface é considerado. O sistema final de equações e não-linear e, com as condições de contorno apropriadas, é resolvido pelo método de Galerkin em elementos finitos e pelo método de Newton. O escoamento é bi-dimensional e, portanto, elementos bi-dimensionais são utilizados para descrever o domínio do problema. Entretanto, para avaliar a concentração ao longo da superfície, foi necessário criar um elemento uni-dimensional. O acoplamento entre estas duas classes de elementos também é discutido. Os resultados mostram que a distribuição de partículas do filme revestido é uma forte função da espessura do filme e das propriedades da suspensão, como a densidade das partículas e coeficientes de difusão. O escoamento de Marangoni pode afetar o padrão de recirculação e a distribuição de concentração de partículas. Além disso, os resultados mostram que a adsorção e dessorção de partículas na interface afetam fortemente a distribuição de partículas.
Slot coating is a common method in the manufacturing of a wide variety of products. It belongs to a class of coating method known as premetered coating: in a steady state operation, the thickness of the coated liquid layer is set by the flow rate fed to the die and the speed of the substrate moving past, and is independent of other variables of the process. For many applications, the coating liquid is a particle suspension. The commom simplified approach is to study the flow as Newtonian and evaluate its viscosity based on the average particle concentration. However, experimental data shows that particle distribution is in fact non-uniform in shear flows. Moreover, particle distribution along the film thickness during the coating process will affect the final fim structure and consequently product performance. Hence, it is important to understand the fundamentals of coating process with particle suspension to better describe and predict the behavior of the flow and the particle distribution in the coated layer. The goal of the present work is to study different particle migration mechanisms in a suspension that may affect particle distribution in the coated film; such as diffusive mechanisms and sedimentation. The model presented takes into account the viscosity dependency and local particle concentration and surface-active particles, i.e. Marangoni effect. Two different approaches were used to study Marangoni flow. First, the bulk-interface transport is considered much faster than bulk diffusion such that the net flux is zero and surface concentration is equal bulk concentration. The second, more complete model, considers adsorption and desorption fluxes from the interface. The non-linear system of equations, with appropriate boundary conditions, is solved by Galerkin Finite Element Method and Newton s Method. The flow is two-dimensional and therefore two-dimensional elements are used to describe flow domain. Nonetheless, in order to evaluate particle concentration along the interface a one-dimensional element was created. The coupling between those two classes of elements of discussed. The results show that the particle distribution on the coated layer is a strong function of the film thickness and suspension properties, such as particle density and diffusion coefficients. The Marangoni flow associated with surface tension gradient due to particle concentration variation along the interface can change the recirculation pattern and particle concentration distribution. Furthermore, the results show that particle adsorption and desorption from interface have a strong effect on the particle distribution.
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Metje, Nicole. "Sediment suspension under water waves." Thesis, University of Birmingham, 2002. http://etheses.bham.ac.uk//id/eprint/5264/.
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Data collected in a large scale laboratory wave flume by a research team using the autonomous bottom boundary layer rig, (STABLE) was the subject of this study. The near bed suspension processes were examined relating them to the hydrodynamics. The deployment of a number of sensors allowed the assessment of their individual performance including the analysis of the pump-sampling and acoustic concentration data. Wavelet analysis was applied to identify the influence of STABLE on the vortex ripples in the vicinity of the rig. It revealed that the modification of the ripple dimensions around STABLE's feet was very localised. Sediment suspension was found to be strongly correlated to wave groups. The measured concentrations and empirical models based on convective and diffusive entrainment mechanisms were compared. A model based on the jet like ejection of particles between a vortex pair was developed and showed that lifting of sediments up to ten ripple heights above the bed was possible. A second model, capable of simulating the pumping effect, included this entrainment process to simulate the suspension under wave groups taking the suspension history into account. The behaviour of neutrally buoyant particles in a laboratory wave flume was videoed and revealed jet like ejections and horizontal movement over two or more ripple wavelengths.
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Nigam, Mats S. (Mats Sandje) 1970. "Numerical modeling of suspension flows." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85307.
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Stephens, Gerard Groves. "Suspension polymerisation in oscillatory flow." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627184.
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Vyas, Saurabh, and Venkata Dinesh Raju Jonnalagadda. "Modelling of Automotive Suspension Damper." Thesis, KTH, Fordonsdynamik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293498.
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A hydraulic damper plays an important role in tuning the handling and comfort characteristicsof a vehicle. Tuning and selecting a damper based on subjective evaluation, by considering theopinions of various users, would be an inefficient method since the comfort requirements of usersvary a lot. Instead, mathematical models of damper and simulation of these models in variousoperating conditions are preferred to standardize the tuning procedure, quantify the comfortlevels and reduce cost of testing. This would require a model, which is good enough to capture thebehaviour of damper in various operating and extreme conditions.The Force-Velocity (FV) curve is one of the most widely used model of a damper. This curve isimplemented either as an equation or as a look-up table. It is a plot between the maximum forceat each peak velocity point. There are certain dynamic phenomena like hysteresis and dependencyon the displacement of damper, which cannot be captured with a FV curve model, but are requiredfor better understanding of the vehicle behaviour.This thesis was conducted in cooperation with Volvo Cars with an aim to improve the existingdamper model which is a Force-Velocity curve. This work focuses on developing a damper model,which is complex enough to capture the phenomena discussed above and simple enough to beimplemented in real time simulations. Also, the thesis aims to establish a standard method toparameterise the damper model and generate the Force-Velocity curve from the tests performedon the damper test rig. A test matrix which includes the standard tests for parameterising andthe extreme test cases for the validation of the developed model will be developed. The final focusis to implement the damper model in a multi body simulation (MBS) software.The master thesis starts with an introduction, where the background for the project is described and then the thesis goals are set. It is followed by a literature review in which fewadvanced damper models are discussed in brief. Then, a step-by-step process of developing thedamper model is discussed along with few more possible options. Later, the construction of a testmatrix is discussed in detail followed by the parameter identification process. Next, the validationof the developed damper model is discussed using the test data from Volvo Hällered ProvingGround (HPG). After validation, implementation of the model in VI CarRealTime and Adams Caralong with the results are presented. Finally the thesis is concluded and the recommendations forfuture work are made on further improving the model.En hydraulisk stötdämpare spelar en viktig roll för att fordonets hantering och komfort. Attjustera och välja en stötdämpare baserat på subjektiv utvärdering, genom att beakta olika användares åsikter, skulle vara en ineffektiv metod eftersom användarnas komfortkrav varierarmycket. Istället föredras matematiska modeller av stötdämpare och simulering av dessa modellerunder olika driftsförhållanden för att standardisera inställningsförfarandet, kvantifiera komfortnivåerna och minska testkostnaden. Detta skulle kräva en modell som är tillräckligt bra för attfånga upp stötdämparens beteende under olika drifts- och extrema förhållanden.Force-Velocity (FV) -kurvan är en av de mest använda stötdämparmodellerna. Denna kurvaimplementeras antingen som en ekvation eller som en uppslagstabell. Det är ett diagram somredovisar den maximala kraften vid varje maxhastighetspunkt. Det finns vissa dynamiskafenomen som hysteres och beroende av stötdämparens förskjutning, som inte kan fångas med enFV-kurvmodell, men som krävs för att bättre förstå fordonets beteende.Denna avhandling genomfördes i samarbete med Volvo Cars i syfte att förbättra den befintligastötdämparmodellen som är en Force-Velocity-kurva. Detta arbete fokuserar på att utveckla enstötdämparmodell, som är tillräckligt komplex för att fånga upp de fenomen som diskuteratsovan och tillräckligt enkel för att implementeras i realtidssimuleringar. Avhandlingen syftarockså till att upprätta en standardmetod för att parametrisera spjällmodellen och generera ForceVelocity-kurvan från de test som utförts på stötdämpartestriggen. En testmatris som innehållerstandardtest för parametrisering och extrema testfall för validering av den utvecklade modellenkommer att utvecklas. Det sista fokuset är att implementera stötdämparmodellen i en multi-bodysimulation (MBS) programvara.Examensarbetet inleds med en introduktion, där bakgrunden för projektet beskrivs ochdärefter definieras målen med arbetet. Det följs av en litteraturöversikt där några avanceradestötdämparmodeller diskuteras i korthet. Därefter diskuteras en steg-för-steg-process för attutveckla stötdämparmodeller tillsammans med några fler möjliga alternativ. Senare diskuteraskonstruktionen av en testmatris i detalj följt av parameteridentifieringsprocessen. Därefterdiskuteras valideringen av den utvecklade stötdämparmodellen med hjälp av testdata från VolvoHällered Proving Ground (HPG). Efter validering presenteras implementeringen av modellen iVI CarRealTime och Adams Car tillsammans med resultaten. Slutligen avslutas rapporten medslutsatser från arbetet och rekommendationer för framtida arbete görs för att ytterligare förbättramodellen.
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Chamard, Thierry. "La suspension des conflits armés." Nice, 1996. http://www.theses.fr/1996NICE0029.
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La difficulté de définir la suspension des hostilités ne tient pas tant à son utilisation dans des circonstances exceptionnelles qu'à son appréciation dans le temps et l'espace. Le droit de la suspension des conflits armés apparaît comme un droit de l'instant, celui ou les armes se taisent et ou la volonté de conciliation se fait dominante. Mais il est aussi adaptation par rapport aux différents types de conflits et à l'idée de paix à instaurer. Droit d'un moment, les modes de suspension des hostilités vont tendre à se muer en moment du droit. Dans le cadre des guerres interétatiques (partie I), si l'exigence minimale est la suspension des hostilités que ces dernières furent negociées ou imposées, seule la fin des combats sera susceptible d'etre negociée. L'adaptation des modes de suspension des hostilités aux conflits internes (partie II) devait générer une évolution originale, menant à une internationalisation accrue. D'abord aboutissement du jeu diplomatique, acte de droit interne indiquant un simple état de fait, l'acte de suspension voit son internationalisation reconnue lors des guerres de libération nationale devenant ainsi non seulement le symbole de la cessation des hostilités mais aussi celui de l'indépendance acquise par la lutte. La fin de la rivalité est-ouest entraîne une recrudescence des conflits internes, mais l'interventionnisme international (d'états ou d'organisations) est rendu possible par des blocages onusiens. Préalable au jeu diplomatique, l'acte de suspension devient à la fois un acte de pacification et de reconstruction. L'ambition purificatrice est donc la constante des actes de suspension des hostilités et justifie leur adaptation a des réalites diverses (nationales, ethniques, internationales). Cette ambition aboutira-t-elle ? Le propre d'une société historiquement viable n'est-elle pas son aptitude à imposer sa paix ?
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Mba, Owono Charles. "La suspension des obligations contractuelles." Nancy 2, 1993. http://www.theses.fr/1993NAN20001.
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Le phénomène de la suspension des obligations contractuelles présente deux caractères principaux : il est à la fois divers et unitaire. Diversité des techniques mais aussi des objectifs, qui s’explique par la multiplicité des types contractuels et par la variété des causes de suspension. à chaque catégorie de contrats, à chacun des objectifs visés, à chacun des obstacles qu’il s’agit de contourner peut correspondre une technique de suspension appropriée. La suspension peut ainsi prendre la forme de modalité d’une obligation, constituer un tempérament à la force obligatoire d’un engagement contractuel ou une alternative à la rupture du contrat. Il y a cependant unité de la notion de suspension, notamment en ce qui concerne le régime juridique des obligations suspendues. Certes toutes les causes de suspension ne sont pas régies par les mêmes règles et ne produisent pas des effets strictement identiques. Mais dans tous les cas, il s’agit d’une solution conservatoire qui, tout en privant l’acte contractuel des effets qu’il est appelé à produire, lui conserve le minimum de vitalité nécessaire a une exécution future. La finalité est en définitive l’accomplissement correct et complet des engagements pris de part et d’autre. La suspension des obligations contractuelles met donc la flexibilité au service du contratThis study about "the suspension of contractual obligations" has permitted to clear the principal characteristics of this notion. The suspension is first varying because it is carry into effect through a variety of technics which have different aims. There is also unity of the notion on the level of the juridical regime about the affected obligation because the state of the contractual relationship is similar in all cases
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JUFFROY, CORINNE. "Sedimentation d'une suspension - effet boycott." Paris 7, 1994. http://www.theses.fr/1994PA077323.
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L'objectif de cette etude est de mettre en evidence les consequences de l'effet boycott en rheologie des milieux disperses. Il est possible d'augmenter le rendement du mecanisme de la sedimentation en realisant des dispositifs constitues de recipients a parois inclinees. On a pu ainsi verifier que le processus de sedimentation s'effectuait beaucoup plus rapidement dans une cuve inclinee que dans une cuve verticale dans les memes conditions. En effet, une fraction des particules se depose sur la paroi inferieure du recipient sous l'effet de la gravite et forme ainsi une fine couche de sediment. Simultanement, il apparait le long de la paroi superieure du recipient une couche marginale de fluide anime d'un mouvement de convection ascendant. On observe alors une acceleration du processus de sedimentation. Ce phenomene est connu sous le nom d'effet boycott. Nous avons pu l'observer lors de l'etude de la sedimentation entre deux cylindres coaxiaux en rotation. L'acceleration normale a l'axe du cylindre induit la formation d'une couche de sediment le long de la paroi externe du cylindre et d'une couche marginale de fluide le long de la paroi interne. Nous avons, dans un cadre experimental et theorique, mis en evidence l'effet boycott pour des suspensions concentrees de spheres rigides et de particules susceptibles de floculer. Nous avons ensuite etudie la fluidisation solide-liquide dans une colonne verticale puis dans une colonne inclinee afin de montrer l'analogie existant avec le phenomene de la sedimentation
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Goulou, Patrick Gabin. "L' esthétique de la suspension." Bordeaux 3, 2009. http://www.theses.fr/2009BOR30026.
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La suspension se veut comme un écart, une prise de distance de Samuel Beckettvis à vis des accents et procédés stylistiques hérités des romans réalistes. L’esthétique de la suspension retravaille et déplace les normes, les frontières génériques du langage. Plus, le Nobel de Littérature 1969 pointe de façon singulière et magistrale la question de l’échec des mots. Avec Beckett, le langage qui était pressenti comme vecteur de la communication devient soudainement inaudible, c’est-à-dire que sa fonction de signification se trouve suspendue,mettant en doute la valeur cognitive des mots, leur cohérence et leur cohésion. Tous ces éléments de signification se trouvent violemment écartés du discours. Parfois la phrase est longue, inachevée, faite de subordonnées sans principale. Le personnage n’est plus facilement repérable. Loquace, il atteint cependant une extraordinaire complexité au fur et à mesure qu’on tente de le cerner. S’il doit parler, il ne parle plus que d’une voix neutre, blanche. A travers ces éléments qui touchent à la nature de la narration, c’est le roman qui se délite et se clôt sur lui-même. La narration qui sourd dans les récits n’est plus que bourdonnement, murmure. La suspension se conçoit donc comme une césure épistémologique, une rupture syntaxique qui témoigne d’une révolution du langage, voire d’un basculement du sens. Le projet beckettien est à ce titre porteur d’émancipation du sujet. Son avènement passe par le dépassement et la mise à mort des sphères du savoir. L’écriture moderne de Beckett fait le constat de l’échec, du vacillement des grands récits de légitimation de la vérité et du sacréSuspension is meant as subversion, aloofness of Samuel Beckett vis à vis stylistic techniques inherited from the realistic novels. The aesthetics of suspension revises and changes norms, generic meanings of language. Moreover, the 1969 Nobel Prize for literature addresses in a singular and masterful way the question of the failure of words. With Beckett, language which was viewed as vector of communication becomes suddenly inaudible, that is its function of meaning is suspended, thus questioning the cognitive value of words, their coherence and their cohesion. All these elements of meaning are abruptly dismissed from the standard language. The sentence is sometimes long, unfinished, made from subordinates without a main clause. The character is not easily discernible any more. Voluble, he/she, however, becomes an extraordinary complexity as one tries to understand her/him. If she/he has to speak, it is with a neutral and toneless voice. Through these elements which affect the narrative mode, the novel disintegrates, closes on itself. Soundless in narratives, narration has simply become humming, murmur. The suspension is to be seen as an epistemological infringement, a syntactic break which testifies a subversion of language, even a shift of meaning. The Beckettian project brings emancipation to the character. Its advent goes through the overtaking and the killing of the spheres of knowledge. Beckett’s modern style highlights the defeat and the wavering of great narratives about the legitimisation of truth and the sacred
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Faure, Fabien. "Suspension magnétique pour volant d'inertie." Grenoble INPG, 2003. http://www.theses.fr/2003INPG0079.
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Le stockage d'énergie est omniprésent dans les installations électriques actuelles. A cet effet, plusieurs laboratoires se sont associés afin de réaliser un système de stockage d'énergie par volant d'inertie. Le but de cette thèse a été de réaliser une suspension magnétique à faible coût de production et à consommation électrique nulle ou du moins la plus réduite possible. Cette suspension, destinée au maintient du volant d'inertie en rotation, doit permettre d'éliminer partiellement les roulements à billes afin de s'affranchir de l'usure et de la dissipation d'énergie par frottement. A cet effet, une étude approfondie des phénomènes statiques et dynamiques a été nécessaire du fait des nombreux phénomènes électromagnétiques et mécaniques déstabilisant. Enfin, la réalisation d'un prototype de suspension magnétique nous a permit de tester et caler nos modèles et de faire apparaître les avantages et inconvénients de la géométrie choisie
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Sabry, Randa. "Stratégies discursives : digression, transition, suspension." Paris, EHESS, 1987. http://www.theses.fr/1987EHES0073.
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Clarenc, Nathalie. "La suspension des engagements internationaux." Thesis, Paris 2, 2015. http://www.theses.fr/2015PA020057.
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Il s’agit d’une étude de droit des actes juridiques internationaux (engagements conventionnels et unilatéraux), portant sur un mécanisme largement utilisé dans la pratique conventionnelle mais très peu étudié en doctrine, celui de la suspension, distingué des mécanismes, plus radicaux mais finalement moins intéressants peut-être, d’extinction des engagements. Pour la première fois, est proposée une définition de la suspension, préalablement distinguée des notions voisines avec lesquelles elle a souvent été confondue (dispense, exception d’inexécution, force majeure, contre-mesures, réserve, etc… et surtout, dénonciation et retrait). La définition proposée fait état des caractéristiques de la suspension telle qu’elle se donne à voir dans les clauses conventionnelles, la pratique diplomatique et la jurisprudence, et prend appui sur la « théorie de l’engagement ». L’étude vise également à clarifier le régime de la suspension, duquel Fitzmaurice disait qu’il soulevait de « graves difficultés de classification et de plan ». L’examen de la pratique révèle en effet que ce régime n’est pas unique mais dual, originalité qui ne manquera pas de frapper la curiosité du lecteur, et dont la mise à jour permet une meilleure compréhension du phénomène de suspensionThis study focuses on a mechanism frequently used in legal practice, but, surprisingly, often ignored in international doctrine: suspension. The mechanism of suspension is to be distinguished from more radical, but arguably less interesting mechanisms, such as revocation. Suspension will be analysed within the context of both conventional and unilateral international law commitments. For the first time, a general definition of suspension will be proposed, which sets it apart from the many similar notions with which it has been confused, such as dispense, exception of inexecution, force majeure, countermeasures, reservations, …, and last but not least, denunciation and withdrawal. The proposed definition also aims to identify characteristics that are unique to suspension, as shown in treaty clauses, in diplomatic practice and case law, and as supported by « commitment theory ». The study will also clarify the legal regime of suspension, which, according to Fitzmaurice, involves « serious difficulties of classification and content ». Indeed, a closer look at suspension in practical terms reveals that there are not one, but two legal regimes of suspension. This eye-opening conclusion will not fail to engage the reader’s interest and will contribute to our further understanding of the phenomenon of suspension
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Zhang, Yi. "Suspension dewatering with aggregate densification." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/suspension-dewatering-with-aggregate-densification(7599d818-8f26-4e2d-b80f-b4fa243dba52).html.
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This thesis concerns design of two pieces of suspension dewatering equipment (i.e. transient batch settlers and steady state continuous gravity thickeners). In a transient batch settler, very slow densification of aggregates within the suspension is considered whilst the drag on the solids in the suspension is assumed to be negligible. The interface of the suspension is then determined by a balance between gravity and the gradient of the compressive yield stress of the gelled suspension. The compressive yield stress functional form in general could be either a weakly gelled formula, or a strongly gelled formula. These formulae differ in the way they behave for solids concentrations in the neighbourhood of the suspension gel point. The effects of the above two gel formulae, the evolution of the compressive yield stress functional form over time during aggregate densification, different initial suspension heights, and different initial feed solids volume fractions upon the predictions of consolidated bed structures and solids volume fractions obtained at the bottom of a batch settler, and upon the evolution of the heights of the suspension and the consolidated bed have been explored. A sufficiently tall initial suspension height might lead to insignificant increases in the solids volume fractions obtained at the bottom of batch settlers after time-dependent aggregate densification. The interfaces of the suspension and the consolidation zone coincide after aggregate densification if the gel point, which increases with time, is larger than the initial feed solids volume fractions. Moreover, the maximum permitted underflow solids fluxes predicted from steady state thickeners have been investigated and compared. Pre-shearing of aggregates which densifies aggregates to have smaller diameters upon entering the thickener is necessary if large underflow solids fluxes and small underflow solids volume fractions are specified. The solids volume fraction at the top of the consolidated bed which is the densified gel point is influenced by the extent of pre-shearing of aggregates. An algorithm for determining this densified gel point has also been developed. In reality, thickeners contain not just a consolidating bed, but also a hindered settling region above it. When the hindered settling region is considered in a thickener, the effects of the extent of aggregate densification that has occurred in the hindered settling region and how that impacts upon thickener performance and sludge rheological properties have been explored in this thesis. A new algorithm for predicting the densified gel point obtained at the top of the consolidated bed has been developed when the hindered settling region is present. The effects of underflow solids volume fractions, aggregate densification rate parameters and pre-shearing of aggregates upon the predictions of maximum permitted underflow solids fluxes, sludge rheological properties, and thickener performance have been explored. The predictions of thickener performance using both the weakly and strongly gelled formulae have also been achieved. In cases where it is possible to neglect the hindered settling region, substantial increases in the maximum permitted underflow solids fluxes, and substantial decreases in the consolidated bed heights and the total solids residence times have been achieved after aggregate densification for a comparatively small underflow solids volume fraction. The benefits arising from aggregate densification are more modest if the underflow solids volume fraction is larger. On the other hand, when the hindered settling region is included, more densification of aggregates occurring in the hindered settling region might lead to taller consolidated bed heights for a specified suspension flux and a specified aggregate densification rate parameter due to higher underflow solids volume fractions.
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Subramanian, Ganesh. "Inertial effects in suspension dynamics." Diss., Pasadena, Calif. : California Institute of Technology, 2002. http://resolver.caltech.edu/CaltechETD:etd-07042002-114141.
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Sabry, Randa. "Stratégies discursives digression, transition, suspension /." Lille 3 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37609641s.
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Abouel-Nour, Aly. "Active control of vehicle suspension." Thesis, University of Leeds, 1989. http://etheses.whiterose.ac.uk/2552/.
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Various types of actively controlled suspension systems for automotive or agricultural applications are theoretically studied on the basis of the well known quarter car model subjected to realistic inputs chosen to represent road surface/forward vehicle speed combinations for a range of different conditions. The vehicle response is evaluated through the performance criteria (the ride comfort, dynamic tyre load and suspension working space) and power requirements (the power input to actuator, power dissipated in damper or actuator and power fluctuation in spring and tyre). The range of suspension systems includes fully active, semi-active, slow-active, single state feedback active, two state switchable damper, continuously variable damper and conventional passive. Computer programmes relating to the general dynamic modelling of ground vehicle suspension systems (generation of the artificial road, random process analysis and human response criteria) are designed. Computer programmes relating specifically to vehicle ride (linear or non linear), derivation of responses and power calculations for linear or non linear models, as well as performance criteria and optimal control of vehicle suspension are also designed. The switchable damper system which involves continuously switching between two discrete settings is of considerable interest because such dampers are currently available. It is shown to offer worthwhile improvements over passive systems in terms of ride performance if a simple control law is followed. Linear optimal control theory is used to obtain the optimal feedback gains of the fully active and slow-active suspension systems. The behaviour of the fully active linear control systems and the possibility of improving their performance by using a non-linear control law is investigated. The performances of the four and two state feedback slow-active systems, using an actuator with limited frequency response up to 3 Hz, are similar. In terms of the power demand, there is little difference between the fully active and slow-active systems, configured with a conventional passive spring in parallel with the actuator, and their ride performances are also similar. The behaviour of the semi-active systems are evaluated with a control law based exactly on the optimal control of the fully active system, except that no power input is available. A method of comparing performance and power requirements is based on the practical viewpoint that the suspension designer is essentially allocated a given amount of working space and must optimise the suspension within this constraint. Hence, all the competing systems are compared on the basis of equal workspace contours. Conclusions and suggestions for further work are discussed with particular reference to the relationship between the predictive models and their practical usefulness in assisting the designer of advanced suspension systems for on and off - road vehicles.
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Hashim, Shahrir. "Drop mixing in suspension polymerisation." Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/34911.
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Suspension polymerisation is one of the major processes used to produce polymers. In this process, monomer is suspended as liquid droplets in a continuous water phase by mean of strong agitation and the presence of a suspending agent. As the suspension polymerisation proceeds, the viscosity of a monomer–polymer droplet increases with conversion. Hence, the physical behaviour of the droplet changes during the process. When new dispersible material is added to the existing suspension drops, the new material and existing drops can remain segregated for significant amounts of time. This will affect the properties of polymer products. The aim of this project was to study the behaviour of drop mixing when new material is added to the existing suspension polymerisation. This study concentrated on the effect of the dispersed phase viscosity on the drop mixing, but agitation intensity and surface stabilities were also important.
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Fang, Hongfei. "Simulation of colloidal suspension systems." Thesis, Curtin University, 2010. http://hdl.handle.net/20.500.11937/1136.
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The research work is focused on the development of a simulation platform for colloidal suspension. Based on discrete element method (DEM), the model developed takes into account the crucial interactions, i.e. the electrostatic repulsion, van der Waals attraction, Brownian force, hydration effects and hydrodynamic force. The mechanism of colloid particle diffusion in confined space and the combined influences of fluid flow field, geometrical confinement, and the interparticle interactions on the self-assembly process are investigated.
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Mouroko-Mitoulou, Thomas. "Filtration de suspensions minérales avec formation d'un gâteau liquéfiable : cas d'une suspension de carbonate de calcium." Compiègne, 2002. http://www.theses.fr/2002COMP1430.
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L'importance économique croissante des suspensions colloi͏̈dales hautement concentrées, a conduit à la recherche des procédés alternatifs à la concentration (déshydratation) thermiqueo Les suspensions faiblement ou moyennement concentrées ont été déshydratées en présence de dispersants par des procédés mécaniques à faible consommation d'énergie utilisables sur filtre-presse (filtrationcompression, accompagné ou non par un champ électrique) en vue d'obtenir des gâteaux hautement concentrés en solides et fluidifiés 0 La filtration-compression en présence de dispersants chimiques (Coatex DV798, Coatex DV806, Coatex DV 67, Coatex DV 765, Coatex DV 834, Coatex DV 828) a permis d'obtenir des gâteaux relativement fluides ayant une siccité comprise entre 69 et 74%. La filtration en présence de dispersants, assistée d'un champ électrique a permis d'obtenir des gâteaux légèrement plus secs que la filtration ordinaire, difficilement liquéfiableso La filtration-compression en présence de dispersants suivie d'une compression assistée d'un champ électrique a permis d'obtenir des gâteaux relativement plus secs que les gâteaux obtenus par filtration-compression Gusqu'à 80% de siccité avec le dispersant cationique Coatex DV 67), mais non liquéfiés. La présence des agents dispersants en amont d'un procédé de filtration-compression s'accompagne d'une perte de dispersant dans le filtrat, qui rend presque inévitable la mise aux normes de ces quantités de filtrats difficilement recyclables. Finalement un procédé original à été mis au point à savoir la filtration en deux étapes qui consiste à former un seul gâteau par la filtration successive de deux suspensions: la première ne contient aucun agents dispersant, contrairement à la deuxième suspensiono Ce procédé à été modélisé et appliqué aussi bien sur les suspensions du carbonate de calcium que certaines autres suspensions de particules minérales (le carbonate de calcium précipité, le carbonate de calcium "OMY A 50", le kaolin, l'hydroxyde d'aluminium et le dioxyde de titane)o Comparativement aux résultats de la filtration en une seule étape, les siccités des différents gâteaux sont sensiblement voisines en revanche la viscosité des gâteaux obtenus par filtration en deux étapes est améliorée et contrairement aux filtrats totalement contaminés de la filtration en une seule étape, la quantité de filtrat lors de la filtration en deux étapes est fortement réduite et donc facilement recyclableo Les résultats obtenus au laboratoire ont été confirmés à l'échelle de filtre-presse pilote, en outre les gâteaux formés ont été comparés aux gâteaux obtenus par concentration thermique des suspensions, principalement leur stabilité sur une période de 8 jourso En plus du fait de la facile application, le concept de la filtration en deux étapes est peut être appliqué à la défloculation in situ ainsi qu'au lavage des gâteaux de filtration.
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Walther, Christa G. "Adaptation to suspension growth : analysing the surface of suspension growth adapted Chinese hamster ovary cells." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4193/.
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Many bio-pharmaceutical production processes are based upon the use of mammalian cell lines, such as Chinese hamster ovary (CHO) cells, capable of proliferation as single cells in suspension in a synthetic environment. Routine use of CHO cells as production vehicles requires a lengthy “adaptation” process from the wild-type adherent clone to clones capable of proliferation in a suspension environment depleted of exogenous growth factors and cell-matrix contacts. Different approaches have been applied in this study to gain a better understanding of the changes on the cell surface occurring as a response to changes in their environment, comparing four cell lines (CCL61, AML, S cells and CHO-S) adapted to suspension or adherence growth condition. Biochemistry and mass spectrometry methods showed differences in surface protein composition for the cell lines. The comparison of the expression of cell-to-cell adhesion molecules revealed a highly variable bimodal distribution on S cells which was not seen on CCL61. Analysis of the expression level of integrins, the main interaction partner of serum components, indicated that integrin expression is not generally down-regulated on suspension-adapted CHO cells. The integrin conformation on the cell surface, analysed by confocal microscopy, revealed a specific conformation, especially with regard to integrin beta 1, characterised by an even, net-like distribution of integrin clusters over the surface of the cells. This specific integrin conformation, which has only been found on suspension-adapted cells, was underlined by a sub-cortical sheet of actin, forming a ball-like structure directly under the cell membrane; this actin conformation required re-organisation of the actin cytoskeleton from a typical fibrillar morphology in adherent cells. The actin content was higher in suspension cell lines compared to adherent cells, but actin up-regulation was also found in non-suspension adapted cells after they had been transferred into suspension. Sphere-like integrin beta 1 clustering on CCL61 grown in suspension could be induced by treatment with cytochalasin D, followed by suspension culture without the drug, however, despite the change in integrin beta 1 conformation these cells could not grow in suspension. The data suggests that adaptation to suspension growth requires conservation of integrins, presumably with respect to their role as structural elements anchoring the plasma membrane to the sub-cortical actin sheath, but it also requires additional changes in the interplay between integrin beta 1 and actin, for example, changes in the regulation of the associated proteins for successful suspension adaptation of CHO cells.
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Klein, Axel. "Transport d’une suspension active de bactéries en milieu confiné." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0137.
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Les propriétés de transport d'une suspension de bactéries motiles sous écoulement présentent un enjeu scientifique fondamental dans la compréhension de la colonisation de nouveaux milieux par ces microorganismes. De nombreuses études font part du comportement singulier de ces suspensions actives en écoulement. L'accumulation aux parois, les comportements collectifs, la modification du comportement rhéologique sont d'autant de phénomènes qui révèlent la richesse de ces systèmes. Malgré tout, de nombreuses questions subsistent. Dans ce travail de thèse, nous présentons l'effet d'un écoulement sur le transport d'une suspension de bactéries Escherichia coli motiles en milieu confiné. Des expériences ont été menées en cellule de Hele-Shaw pour comprendre l'influence du Péclet hydrodynamique et du Péclet de confinement sur le transport de la suspension en écoulement de Poiseuille. Les propriétés de nage d'E. coli ont été caractérisées dans un fluide à l'équilibre par deux techniques optiques de mesures non-intrusives : le tracking et la microscopie dynamique différentielle. En écoulement, ces propriétés se voient être fortement modifiées et dépendantes du cisaillement. L'effet de rhéotaxie a été mis en évidence et favorise la migration bactérienne à contre-courant aux parois ; migration retrouvée également loin des surfaces. Nous montrons également que le confinement de la suspension influe sur l'épaisseur de la couche limite qui, couplé à l'intensité de l'écoulement, modifient la distribution en bactéries dans la cellule de Hele-ShawThe transport properties of a suspension of motile bacteria under flow are a fundamental scientific issue in order to understand the colonisation of new environments by microorganisms. Numerous studies report the singular behaviour of these active suspensions in flow. Accumulation at the walls, collective motion, modification of the rheological behaviour are all phenomena that reveal the richness of these systems. Nevertheless, many questions remain. In this thesis, we present the effect of a flow on the transport of a suspension of motile Escherichia coli bacteria in confined geometries. Experiments were carried out in a Hele-Shaw cell to understand the influence of flow and confinement Peclet numbers on the transport of the suspension in a Poiseuille flow. The swimming properties of E. coli were characterised in a fluid at rest using two non-intrusive optical techniques: tracking and differential dynamic microscopy. In flow, these properties are strongly dependent on shear. Rheotaxis effect has been pointed out at the vicinity of a surface and favours upstream swimming; upstream migration also found in the bulk. We also show that confinement of the suspension influences the thickness of the boundary layer and, with the intensity of the flow, modifie the distribution of bacteria through the Hele-Shaw cell
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Vieira, Danilo Martins. "Sistema ativo de auto-estabilização para veículos suspensos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-11082010-151256/.
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Durante as últimas décadas, têm sido realizados vários estudos sobre a aplicação de veículos suspensos como em teleféricos, bondinhos, linhas de transporte e/ou montagem em indústrias, e robôs para finalidades diversas. Como veículos suspensos possuem comportamento de pêndulo, estão suscetíveis as ações de forças externas que geram oscilações e balanços indesejados no veículo que podem comprometer sua função e segurança. Um levantamento bibliográfico mostrou a deficiência de estudos de sistemas que mantenham a estabilidade física de veículos suspensos. Usando conceitos de conservação de energia e quantidade de movimento foi concebida a ideia de desmembrar o corpo do veículo suspenso em duas partes, uma massa fixa e uma massa móvel de atuação e estabilização da estrutura do veículo; dessa forma fazendo uso apenas de componentes internos ao veículo, uma vez que em sistemas suspensos é grande a dificuldade de aplicação de forças externas para correção de posicionamento. Neste trabalho foi desenvolvido um sistema ativo de autoestabilização para veículos suspensos capaz de amenizar os efeitos de forças externas que possam comprometer a atividade desempenhada pelo veículo. Para a autoestabilização foi montado um sistema de controle em malha fechada com sensor de detecção de inclinação (posição) e atuador com motor de corrente contínua para deslocar uma massa móvel dentro do robô suspenso, acionados por um microcontrolador embarcado. A eficiência do sistema foi comprovada com a montagem de um protótipo, onde uma programação baseada em controle proporcional e derivativo foi suficiente para garantir uma eficiente e rápida estabilização no robô quando sujeito a forças externas como atuação de ventos, por exemplo.During the last decades, many researches and studies have been done about suspended vehicles such as chair lifts, cable cars, carrying and assemblies of parts in the industry, etc. Suspended vehicles behave like a pendulum and they are susceptible to the action of external forces which cause oscillations and unwanted swing at the vehicle that may affect function and security of the vehicle. For several applications it is important to keep the physical stability of suspended vehicles (or part of them), such as in autonomous robots for inspection. In suspended systems it is very difficult to apply external forces to correct its position due the swing; so, it is proposed a new stabilizing system for suspended vehicles based on the conservation of energy and quantity of motion. Using only internal components of the suspended vehicle, the mass of the system was separated in two parts: an active mobile part that stabilizes a fixed part such as the structure of the vehicle. In this work, it is described an active system for swing control on suspended vehicles, able to soften the effects of external forces that can dangerously damage the performance of the vehicle. An autonomous off-board microcontroller with feed-back program was assembled to stabilize the structure of the vehicle by using an inclination sensor attached to it. A DC motor is used to move the mobile part of the suspended vehicle to correct the equilibrium of the vehicles structure. The microcontroller program based on proportional-derivative control system was implemented and tests were performed on a prototype vehicle. A good performance of the system was obtained with an efficient and fast stabilization of the prototype structure under the action of external forces, such as wind forces.
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Salahuddin, Asif. "Orientation and rotational diffusion of fibers in semidilute suspension." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41163.
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The dynamics of fiber orientation is of great interest for efforts to predict the microstructure and material properties of a suspension flow system. In this research a fiber-level, hybrid simulation method, LBM‒EBF (coupled lattice‒Boltzmann method with the external boundary force method) is undertaken to advance the current understanding of the hydrodynamic interaction induced rotational diffusion mechanism for rigid fibers in semidilute suspension of low Reynolds number flow. The LBM‒EBF simulations correctly predict the orbit constant distribution of fibers in a sheared semidilute suspension flow. It is demonstrated that an anisotropic, weak rotary diffusion model can fit the orbit constant distribution very well, but it can not describe the asymmetry in Stokes flow observed in semidilute suspension. The rotational diffusion process is then characterized with a three dimensional spatial tensor representation of the rotational diffusivity. A scalar measure of the rotational diffusion‒'scalar Folgar‒Tucker constant', C[subscript I], is extracted from this tensor. The study provides substantial numerical evidence that the range of C[subscript I] (0.0038 to 0.0165) obtained by Folgar&Tucker (J. reinf. plast. and comp, v.3, 1984) in a semidilute regime is overly diffusive, and that the correct magnitude is of O(10⁻⁴). The study reveals that the interactions among fibers become more frequent with either the decrease of fiber aspect-ratio, r[subscript p] (keeping nL³ constant, where n is the fiber number density, and L is the fiber length) or with the increase of nL³ (keeping r[subscript p] constant) in the semidilute regime, which in consequence causes an increase in C[subscript I]. The rheological properties of sheared semidilute suspension are also computed with direct LBM‒EBF simulations. The LBM‒EBF investigation is extended to characterize the fiber orientation in a linearly contracting channel similar to a paper machine 'headbox'. It is found that the rotational diffusion is the predominant term over the strain rate in the semidilute regime for a low Reynolds number flow, and it results in a decreasing trend of rotational Peclet number, Pe, along the contraction centerline. Lastly, in order to improve the numerical consistency of the existing LBM‒EBF approach, a modification to the body force term in the LB equation is suggested, which can recover the exact macroscopic hydrodynamics from the mesoscale.
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Rizzo, Audrey. "L'approche CRONE dans le domaine des architectures complexes des suspensions de véhicules automobiles : la suspension CRONE Hydractive." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14564/document.
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Cette thèse s'inscrit dans la continuité des travaux de l'équipe CRONE appliqués à la suspension. Cette thèse permet de proposer une suspension CRONE qui non seulement gère le compromis Isolation vibratoire/ tenue de caisse mais également isolation vibratoire/ tenue de roue. Pour cela un critère est développé sur la tenue de roue, applicable à tous types de suspensions permettant l’analyse et le dimensionnement de la suspension pour le contrôle de roue. De plus afin de lever le dilemme entre sollicitations route et sollicitation conducteur, une stratégie pour les suspensions bi -états est proposée et appliquée sur suspension hydractive. Enfin , un travail de formalisme de l’ influence la suspension sur la dynamique véhicule fut réalisé permettant d ’enrichir la stratégie de commutation déjà développée pour agir en virage et en freinage et ainsi optimiser l’utilisation de la suspensionThis thesis follows some previous work of the CRONE team applied to carsuspensions. It allows to purpose one car suspension, called CRONE car suspension, whichimproves the compromise between low frequency road filtering and car holding and thecompromise between hight frequency road filtering and wheel holding. To hold the wheel acriterium on the wheel holding is developed. This criterium can be used to analyse and tunedall kind of car suspension around the wheel pulsation. Moreover, to fight against thecompromise between the driver input and the raod input, a control laws is developed andapplied to a bi-state car suspension called hydractive car suspension. Finally, the influence ofthe car suspension tuning on the vehicle dynamic and more precisely on the ESP, ABSsystems is studied and illustrated with some first experiments
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Alirand, Marc. "Etude par les bond graphs d'une suspension Citroën et conception d'une suspension à correction d'assiette active." Lyon 1, 1991. http://www.theses.fr/1991LYO10012.
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Brezas, Panagiotis Panos. "Time-domain optimal control for vehicle suspensions." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607986.
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Do, Anh Lam. "Approche LPV pour la commande robuste de la dynamique des véhicules : amélioration conjointe du confort et de la sécurité." Electronic Thesis or Diss., Grenoble, 2011. http://www.theses.fr/2011GRENT114.
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Ce travail concerne le développement de méthodes de commandes avancées pour les suspensions automobiles afin d'améliorer la tenue de route des véhicules et le confort des passagers, tout en respectant les contraintes technologiques liées aux actionneurs de suspension (passivité, non-linéarités, limite structurelle). Dans la 1ère partie, nous proposons deux schémas de commande par approche LPV polytopique (Linéaire à Paramètre Variant) et Stabilisation Forte (Strong Stabilization) avec optimisation par algorithme génétique pour résoudre les conflits confort/tenue de route et confort/débattement de suspension. Dans la 2ème partie, pour résoudre le problème complet de commande de suspensions semi-actives, nous développons d'abord une stratégie générique pour les systèmes LPV généraux soumis à la saturation des actionneurs et à des contraintes d'état. Le problème est étudié sous la forme de résolution d'inégalités linéaires matricielles (LMI) qui permettent de synthétiser un contrôleur LPV et un gain anti wind-up garantissant la stabilité et la performance du système en boucle fermée. Ensuite, cette stratégie est appliquée au cas de la commande des suspensions semi-actives. Les méthodes proposées sont validées par une évaluation basée sur un critère industriel et des simulations effectuées sur un modèle non-linéaire de quart de véhiculeThis work concerns the development of advanced control methods for automotive suspensions to improve road holding and passenger comfort, while satisfying the technological constraints related to the suspension actuators (passivity, nonlinearity, structural limit). In the first part, we propose two control schemes by polytopic LPV (Linear Parameter Varying) approach and by Strong Stabilization with genetic algorithm optimization to solve the comfort/handling and comfort/suspension travel conflits. In the second part, to solve the full semi-active suspension problem, we develop first a generic strategy for general LPV systems subject to actuator saturation and state constraints. The problem is studied in the form of resolution matrix of linear inequalities (LMI) that allows synthesizing an LPV controller and an anti-windup gain to ensure the stability and performance of the closed-loop system. Second, the theoretical result is applied to the case of semi-active suspension control. The proposed methods are validated by an evaluation based on an industrial standard and simulations on a nonlinear quarter vehicle model
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Share, Hanli. "Suspension as an unfair labour practice." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1018655.
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Suspension as a form of an unfair labour practice can be of two categories. There could be a situation where an employer suspends an employee as a disciplinary sanction after an employee has committed an act of misconduct. This is often referred to as a punitive suspension. An employer may also suspend an employee pending a disciplinary hearing. In this case the employee has not yet been found guilty because the investigation into the alleged misconduct is still on going. The employee may be suspended as a way of preventing him from interfering with the investigation process into the alleged misconduct. This form of suspension is often referred to as a preventative suspension. It is very important to note the distinction between the two forms of suspension because the processes that are followed when effecting them are different. Failure to acknowledge the difference might result in a situation where an employer might be effecting a preventative suspension but the consequences might be that of a punitive suspension and end-up being an unfair labour practice. Suspension is a disciplinary measure, and it is important to note that in the event that the employer elects to implement a suspension, its conduct must be disciplinary in nature and intent and should be corrective rather than punitive.Unlike dismissals where the Code of Good Practice of the Labour Relations Act, No 66 of 1995 provides guidance on what constitutes procedural and substantive fairness, there are no guidelines on what constitutes procedural and substantive fairness when it comes to suspensions. This has resulted in a situation where suspension is treated as a minor aspect of disciplinary measures that is frequently abused as it is often on full remuneration. This, however, does not allow an employer to suspend employees at will, without merit and without following proper procedure. Suspension could have severe adverse effects on employees and often affects their reputation, goodwill, human dignity, self-esteem and the right to meaningful association and work. It is for this reason that suspension must be effected in a way that is procedurally and substantively fair.Punitive suspension is implemented as a sanction and is often without pay and is a last resort prior to dismissal. Preventative suspension occurs prior to a disciplinary hearing, with the aim of temporarily removing the employee from the workplace to enable the employer to conduct a proper investigation without interference. Unfortunately preventative suspensions are often abused by employers in that they protract over extended periods of time, making the preventative suspension punitive in nature, to the extent that the courts have been forced to intervene and lay down stringent requirements that must be met in order to prevent such abuse.There are various requirements for suspension which range from the intention of the employer, the audi alteram partem rule, sufficient reasons prior to suspension to period of suspension. Most employment relationships are governed by disciplinary codes or collective agreements, which often place limitations on the concept of suspension. Some codes provide for special leave at the option of the employee, which the employer often abuses instead of utilizing the preventative suspension option. This, however, is more often than not to suit a political agenda.In the event of non-compliance by an employer, an employee is not left remediless. An unfair suspension constitutes an unfair labour practice and an employee has the right to refer such dispute to the relevant labour forums like the CCMA or the relevant bargaining council. Employees are cautioned not to refer their disputes to the Labour Court for final relief, but rather to only approach the courts for urgent interim relief, like interdicts.