Academic literature on the topic 'Drainage forcé'
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Journal articles on the topic "Drainage forcé"
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Abduraimova, Dilbar, Zaytuna Ibragimova, Makhsud Otakhonov, and Djamila Khusanova. "Deformation processes in open drainages." E3S Web of Conferences 264 (2021): 03010. http://dx.doi.org/10.1051/e3sconf/202126403010.
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The quality and quantity of agricultural products depend on land reclamation. Collector-drainage systems are used to improve the reclamation state of irrigated areas. The article discusses the stability of slopes of open collector-drainage networks in the irrigated lands of the Hungry Steppe. Discussed problems create during construction and providing productivity of drainages system in irrigation fields. The causes of the deformation process are discussed. The deformation process occurring as a result of landslides of the banks of open collectors is estimated. Recommendations for determining the stability of the banks of an open collector are based on the definition of a model of circular cylindrical sliding surfaces. Used statistic law of mechanics in calculation work based on the model of the ground movement around a cylindrical surface. During calculations, the main attention is given to the weight force, hydrodynamic force, and bite force of the ground. Stability coefficient calculated according to keeping moment (М1) moving moment (М2). In determining the stability of the soil, the main factor of the coupling of the adhesion between the soil particles is substantiated. The suffusion process occurring as a result of moistening and salinization of the soil of the shores of an open reservoir is estimated and analyzed, decreasing of stagnation coefficient in a result of ground absorption process. Analyzing soil samples of various salinities under laboratory conditions, soil adhesion was evaluated. Based on the studies, recommendations are given for the restoration of the shores of open drainages. The given recommendations are based on increasing the drainage's resilience and preventing deformation processes from constructing the drainage in slopes.
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Melwyn, Joshua R., R. Rajaperumal, J. Saravanavel, S. M. Ramasamy, and K. Palanivel. "Centrifugal radial drainages and their geological significance in southern Kerala, India." Disaster Advances 16, no. 2 (January 15, 2023): 25–29. http://dx.doi.org/10.25303/1602da025029.
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The drainage fabric is the reflection of the surface and sub-surface geological systems and processes of the Earth. In this context, the State of Kerala, has prolific network of drainages due to the unique physiographic conditions and it was studied to map the drainage fabric and the anomalies using IRS FCC wrapped DEM of SRTM data of the Southern parts of Kerala. The study revealed the occurrence of larger centrifugal radial drainages conspicuously in a number of places. Such drainages seem to indicate the phenomenon of doming due to the still prevalent northerly directed compressive force related to the post collision tectonics and the east north easterly compressive force due to the rising of the Carlsberg ridge in the Arabian Sea. These both forces in combination might have resulted in the phenomenon of simultaneous cross folding leading to the formation of the domes. The active tectonics have serious implications on the natural disasters in general and the tectonically vibrant Kerala State in particular, therefore the drainage anomalies of Kerala warrant demanding studies.
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Gerasimov, Viktor, Evgenii Nizhegorodtsev, and Evgenii Voronov. "The effect made by the interaction between rock and fibrous polymeric materials on the geotechnological processes." Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal, no. 1 (February 17, 2021): 27–35. http://dx.doi.org/10.21440/0536-1028-2021-1-27-35.
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Introduction. When mining by opencast, mining enterprises use dams and dikes to create circulating water settling basins. The settling basins are equipped with layer drainages carrying groundwater off and ensuring stability of structures. Fibrous polymeric materials (geotextiles) can be used as drainages serving as protective and drainage layers in the bases of heaps in the process of metals leaching from rocks. Research methodology. Geotextile drainages are calculated taking into account the uniform pressure from the overlying rock mass. Local deformation of fibrous materials caused by the force action of coarse rocks is not taken into account. Experimental studies of rock pressure on fibrous polymer materials have been carried out. The force measurement system creates the required force, the depth of the cone penetration into the fibrous material is measured using a dial indicator. The materials with a bulk density of 70, 110, 130 kg/m3 were used. Results. Analysis and discussion. The above theoretical studies allow to consider the probable cases of macrocontacts between rock and fibrous media and determine the ratio of local deformation in order to clarify fibrous media sizes and characteristics in future function as drainage and protective materials. Conclusions. Local deformations of fibrous media at the contact points may amount to 30–40% locally reducing the drainage capacity of fibrous material. Therefore, when designing structures made of rock, such as dikes, dams, leaching heaps, it is required to increase the design height of fibrous drainage by 10–30% taking into account macrocontacts with rocks.
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Fernández-Raga, María, Iván García-Díez, Julian Campo, Julio Viejo, and Covadonga Palencia. "Effectiveness of a New Drainage System for Decreasing Erosion in Road Hillslopes." Air, Soil and Water Research 14 (January 2021): 117862212098872. http://dx.doi.org/10.1177/1178622120988722.
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Water is one of the most important erosive agents in roadside hillslopes. When these are built with ineffective drainage systems, erosion occurs, reducing road’s service life. However, these systems are not receiving the appropriate importance, given their strategic value. Therefore, a new drainage system called ‘branched’ is proposed in this study. Its technical and economic feasibility is compared with those of the traditional system, which consists of drainages with lines that follow maximum hillslope, to assess differences in relation to erosion, construction and maintenance costs, and service life. Different parameters were analysed, such as the average velocity of water (mm−1) running through the channels, its average specific energy (kJ), and its drag force (N). A scale model was constructed and used to test these factors before implementing it in natural terrain for testing it under field conditions. According to the theoretical and measured results, these factors were lower in the branched drainage than in the traditional one (from 24% to 34% in speed, from 37% to 60% in energy, and from 51% to 73% in force). The service life of hillslopes with a branched system of up to 0.5 m high and 1:2 grade is significantly longer than in those with a traditional drainage. Although the initial economic expense for the construction of the branched system is higher (€3534/m3 as opposed to €2930/m3 for the traditional one), its maintenance cost will be lower than the traditional one (€1230/m3 per year for the branched one as opposed to €1332/m3 per year for the traditional one). Consequently, under our experimental conditions, the proposed drainage will be profitable from the eighth year of construction, saving on the road maintenance in the following 15 years of service life.
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Schachinger, Tobias, Florian J. Arbeiter, Stefanie Eichinger, and Florian Saliger. "Research on pipe materials for tunnel drainage by the ÖBB Task Force Drainage." Geomechanics and Tunnelling 12, no. 5 (October 2019): 467–71. http://dx.doi.org/10.1002/geot.201900022.
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Han, Tao, Tingting Luo, Tao Zhang, Yong Yan, Xiaoxu Hu, Tao Yan, and Weihao Yang. "Analysis on the Vertical Additional Force of Shaft and Drainage Settlement Characteristics of Topsoil Containing Multiaquifers." Geofluids 2022 (July 25, 2022): 1–32. http://dx.doi.org/10.1155/2022/4884595.
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The vertical additional force induced by the drainage consolidation settlement of the topsoil is one of the main factors for shaft wall fracture. To date, the number of aquifers of topsoil rises with the depth increasing of shaft, which would lead to a more serious additional force effect. Thus, studying the vertical additional force law of the shaft when drainage settlement occurs in its surrounding topsoil containing multiaquifers is of great significance to predicting the shaft stress and guarantying shaft safety. In this study, mechanical analysis of the topsoil with the shaft crossing multiaquifer was carried out, and the settlement of each aquifer and aquiclude was calculated by separating the single-slope drainage consolidation and the double-slope drainage consolidation. Then, the calculation model of vertical additional force was established due to the settlement caused by the reaction of the additional force on the topsoil containing multiaquifers, and the calculation model of shaft wall stress was also developed. Verification of this model was conducted by comparing the filed measurement data of the shaft wall strain and the theoretical data calculated by the stress model. Finally, the effect laws of drainage velocity, central aquifer thickness, location, and number on the additional force were obtained and analysed. This paper is expected to provide theoretical support for predicting the additional force and shaft wall stress during its service time.
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Liu, Shiyang, Xuefu Zhang, Feng Gao, Yun Li, and Dulaimic Al. "Parameter optimization of anti-crystallization flocking drainage pipe based on macro force and displacement characteristics of villus." Thermal Science 25, no. 6 Part A (2021): 4127–35. http://dx.doi.org/10.2298/tsci2106127l.
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The crystal blockage of tunnel drainage pipe seriously affects the smoothness of the whole drainage system. Therefore, it is very important to effectively prevent crystal plugging in tunnel drainage system to ensure the safety and stability of lining structure during tunnel operation. Based on the macro force and displacement characteristics of villus, the optimization of villus diameter and villus length of flocked drainage pipe at low flow rate was studied by numerical simulation. The results show that: there is a difference of 1-2 orders of magnitude between the 3-D displacements of the bottom villus and one order of magnitude between the 3-D displacements of the side villus of the flocked drainage pipe; with the increase of villus length, the 3-D displacement of villus increased parabola and with the increase of villus diameter, the 3-D displacement of villus decreased gradually; the results show that the first and third principal stresses of the bottom villus increase linearly with the increase of villus length, while the first and third principal stresses of the side villus increase parabola with the increase of villus length; when the flow rate is 2 cm/s, the diameter of villus is 0.6 mm and the length of villus is 20 mm. Flocking drainage pipe anti crystal plugging technology fills the blank of tunnel drainage pipe anti crystal plugging research. This technology can reduce the maintenance cost of tunnel drainage system during operation, and ensure the safe and normal operation of the tunnel.
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Han, Tao, Yong Xue, Weikui Lv, Yu Zhang, and Tingting Luo. "Prediction and Analysis of Vertical Additional Force of Shaft Wall in Topsoil Containing Multiple Aquifers during Drainage." Sustainability 15, no. 4 (February 5, 2023): 2877. http://dx.doi.org/10.3390/su15042877.
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Studying the additional force in topsoil containing multiple aquifers can have a significant impact on predicting shaft wall fracture and guaranteeing shaft safety, as the aquifer number increases as drainage occurs. In this study, a numerical model calculating the effect of drainage on additional force in topsoil, containing multiple aquifers, was established on the basis of several practical engineering cases. The changes in the stress displacement of the shaft wall was analyzed during three different stages of shaft construction using typical parameters, and the effects of the various factors on the additional force variation under different water level gap conditions, depending on whether the drainage was synchronized or unsynchronized, were studied. The results indicate that the increment in the additional force, with an increasing water level gap in the central aquifer, is obviously larger than that in the bottom aquifer, and the difference in the maximum additional force between these two aquifers is approximately 0.6 MPa. The increasing number of central aquifers results in a higher increment in this force, which reaches 12 MPa with an increasing number of central aquifers. Meanwhile, a threshold value (about 0.6~0.7 H) exists for the depth of a central aquifer in terms of its effect on the additional force.
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Schachinger, Tobias, Lukas Sperger, Roman Heissenberger, and Oliver Kai Wagner. "Task Force Drainage (TFD) - The project for life after." Geomechanics and Tunnelling 10, no. 6 (November 28, 2017): 779–87. http://dx.doi.org/10.1002/geot.201700045.
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Yang, Yan Min, Run Tao Zhang, Bo Qu, and Jian Ping Sun. "Detection of Mechanical Properties of Reinforced Concrete Pipes and Affected the Quality of Construction." Applied Mechanics and Materials 633-634 (September 2014): 904–8. http://dx.doi.org/10.4028/www.scientific.net/amm.633-634.904.
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Through analyzing construction method specimens parameter detection and external pressure loading test,test drainage construction technical indicators reinforced concrete pipes,cracks load,failure load,local deformation and overall deformation,research and evaluation of the performance of its force drainage construction quality management.
Dissertations / Theses on the topic "Drainage forcé"
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Cohen, Alexandre. "Dynamique rapide dans les mousses liquides : expériences de drainage et de vibration à l’échelle d’un bord de Plateau." Thesis, Nice, 2015. http://www.theses.fr/2015NICE4057/document.
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Je reporte ici une étude expérimentale sur la réorganisation inertielle de liquide dans un microcanal, constitutif des mousses liquides, appelé le bord de Plateau qui est soutenu par trois films de savon. Deux perturbations sont appliquées sur un bord de Plateau. Premièrement, une goutte y est ajoutée. La viscosité du liquide et taille initiale du bord de Plateau et de la goutte sont variés. La redistribution du liquide ajouté est pilotée par les forces capillaires. On observe un régime inertiel où un ressaut hydraulique capillaire se déplace à vitesse et géométrie constantes dans le bord de Plateau. Ce régime est décrit théoriquement et révèle le rôle majeur joué par les films de savon. On observe aussi un régime dominé par les effets visqueux où le liquide ajouté est redistribué selon une dynamique de type diffusive. La transition entre les deux régimes dépend des paramètres de contrôle du système et est caractérisée. La seconde perturbation est acoustique. Une plaque vibrante perturbe le bord de Plateau et les films. La taille du bord de Plateau, la fréquence et l’amplitude de forçage sont variées. Une onde de flexion se propage dans les films qui ont le bord de Plateau pour condition limite fixe ou libre selon sa masse. A haute amplitude, un régime non linéaire apparaît et le liquide dans le bord de Plateau se réorganise en trois zones de taille et d’amplitude d’oscillation très contrastées. Dans chacune des zones, le déphasage entre l’onde dans le film et l’onde dans le bord de Plateau est différent. Le système couplé du film et du bord de Plateau est modélisé par un oscillateur forcé dont la fréquence propre dépend de la fréquence de forçageI report an experimental study of inertial liquid reorganization into a liquid foam microchannel, also called a Plateau border supported by three soap films. Two perturbations are applied on the Plateau border. Firstly, a liquid drop is injected. Liquid viscosity, drop size and Plateau border size are changed. The liquid redistribution is drived by capillary forces. We observe an inertial regime where a capillary hydraulic jump move on the Plateau border with a constant shape and a constant velocity. This regime is modeled and shows the importance of soap films. We also observe a viscous-dominated regime where the added liquid is redistributed with a diffusive-like dynamic. The transition between the two regimes is investigated and qualitatively accounted for. Secondly, the Plateau border and the three films are vibrated by a plate. A bending wave is shown to propagate in the soap films with the Plateau border for free or fixed limit conditions according to its mass. For high amplitudes, a non linear regime appears and the liquid inside the Plateau border is redistributed along three zones of very contrasted size and oscillation amplitudes. In each zone, the phase difference between the wave in soap films and the wave in Plateau border is different. The system composed of films and the Plateau border is modelled by a forced oscillator with a resonance frequency which depends on the forced frequency
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Trinh, Pierre. "Réactions d'oxydation dans une mousse : application à la dissolution du cuivre." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS116.
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La récupération des métaux issus de déchets d'équipements électriques et électroniques (DEEEs) présente un intérêt environnemental et économique. Une des étapes de ce processus est l'hydrométallurgie : les métaux contenus dans les broyats de DEEEs sont lixiviés par des solutions d'acides inorganiques concentrées. Dans ce contexte, les travaux de cette thèse explore l'utilisation d'une mousse liquide pour lixivier le cuivre. Les mousses liquides présentent deux intérêts majeurs : diminuer le volume de déchets liquides et bénéficier du pouvoir oxydant du gaz contenu dans les bulles. Deux réactifs nécessitant la présence de dioxygène pour dissoudre le cuivre ont été étudiés : l'acide chlorhydrique et l'hydroxylamine. Comparé à une solution, nous montrons que les mousses accélèrent la cinétique des réactions de dissolution du cuivre impliquant une phase gazeuse. Cet effet provient d'un transport plus rapide du dioxygène vers le métal. Afin d'étudier plus précisément ces phénomènes de transport, nous avons conçu un montage de drainage forcé. Celui-ci consiste à injecter à débit constant la solution moussante au sommet d'une colonne de mousse. Il permet ainsi d'uniformiser la vitesse du front de drainage dans la mousse. Nous observons alors deux régimes. Dans le premier régime, la quantité de cuivre dissout est limitée par le flux de protons atteignant la surface métallique. Elle augmente ainsi avec le débit imposé. Dans le second régime, cette quantité est limitée par le flux de dioxygène et elle diminue alors avec le débit. La structure de la mousse a donc une influence directe sur la quantité de cuivre dissoutRetrieving metals contained in waste from electric and electronic equipements (WEEEs) is an environnemental and economic challenge. One step of this process is hydrometallurgy : metals contained in crushed WEEEs are lixiviated by concentrated inorganic acid solutions. In this framework, we explore the use of liquid foams for copper lixiviation. Liquid foams have two main advantages : decreasing the liquid waste volume and benefiting from oxidizing properties of the bubble gas. Two reactants that require dioxygene to dissolve copper have been studied : hydrochloric acid and hydroxylamine. Compared to a solution, liquid foams increase the kinetics of copper dissolution reactions that imply a gas phase. This effet is due to a faster dioxygen transport to the metal. To go further into the understanding of these transport phenomena, we designed a forced drainage experimental setup. It consists in injecting the foaming solution at a constant flowrate on the top of a foam column. We then observe two regimes. In the first one, the dissolved copper quantity is limited by the protons flux that reaches the copper surface. Thus, this quantity increases with the set flowrate. In the second regime, it is limited by the dioxygene flux and so it decreases with the flowrate. Thus, the foam structure directly influence the copper dissolved quantity
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Cadart, François-Xavier. "Les wateringues, une association syndicale forcée de propriétaires." Lille 2, 2004. http://www.theses.fr/2004LIL20001.
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Instituées au XIIème siècle, les wateringues doivent être regardées, malgré la critique, comme de véritables établissements publics. Plus que la recherche d'une plus-value, ces associations syndicales forcées de propriétaires exécutent un véritable service public. Leur soumission à un régime juridique et à un mode de fonctionnement particulier révèle le caractère atypique de ces institutions. Si celles-ci sont fortement attachées au concept de propriétés rurales, les mutations de la plaine maritime imposent de réfléchir sur l'évolution des rapports entre ruraux et urbains afin de refonder le système participatif et financier. De même, si les wateringues ont leurs compétences strictement définies par leurs statuts, elles étudient la possibilité de travailler de façon concertée avec les divers acteurs de l'eau afin d'adapter leur mode de fonctionnement aux exigences écologiquesIn spite of certain criticisms, wateringues, created in the 12th century must be considered as genuine public institution. Rather than looking to make a profit, these compulsory landlord's unions offer a valuable service for the community. Their obedience to certain laws and to a specific functioning reveals the uncommon characteristics of these institutions. As those are strongly associated with the concept of rural property, changes of this type of land call for a reflection on the shifts of relationships between rural and urban populations, in order to redefine the participative and financial system. Although the status of wateringues strictly defines the competences, the various water-related participants are thinking of working together in order to adapt their functioning to ecological requirements
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Wong, Chi-leung, and 黃志良. "A study of the feasibility and impact of the contracting out of directlabour force in the Drainage Services Department." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31965374.
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Wong, Chi-leung. "A study of the feasibility and impact of the contracting out of direct labour force in the Drainage Services Department." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19711670.
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Do, Hyunsun. "Development of a turbulent flotation model from first principles." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/28285.
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Flotation is a process of separating particulate materials of different surface properties in a hydrodynamic environment, and is used extensively for separating different minerals from each other in the mining industry. In this process, air bubbles are introduced at the bottom of a particulate suspension (pulp), so that bubbles coated with hydrophobic particles rise to the top and form a froth phase while hydrophobic particles stay in suspension. The selectivity of the flotation process is determined by the hydrophobicity of the particulate materials involved, while the kinetics of the process is controlled by the hydrodynamic conditions and the disjoining pressures in the thin aqueous films between air bubbles and particles.
In the present work, a mathematical model for the flotation process has been developed by considering both the hydrodynamic and surface chemical parameters. The model can describe the events occurring in both the pulp and froth phases of a mechanically-agitated flotation cell. The pulp-phase model is based on predicting the kinetics of bubble-particle attachment using the DLVO extended to include contributions from hydrophobic force and the theory of turbulent collision. The froth-phase model is based on predicting the rate of bubble-particle detachment by considering bubble coarsening and water recovery. The predictions from the overall flotation model are in general agreement with the results obtained in single-bubble flotation experiments and the flotation test results reported in literature. Since the model has been developed largely from first principles, it has predictive and diagnostic capabilities.Ph. D.
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Silva, Deusanilde de Jesus. "Química da parte úmida em processo de fabricação de papel - interações em interfaces sólido-líquido." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-13082010-115730/.
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Um polieletrólito catiônico (poliamina), com baixo peso molecular e elevada densidade de carga, normalmente aplicado como agente coagulante do lixo aniônico, foi usado para estudos de retenção e drenagem na fabricação de papel. O uso do carboximentil celulose de sódio para simulação do teor de lixo aniônico e seu efeito na retenção de cargas minerais foi uma característica importante para este trabalho. Pode ser observado que o aumento da dosagem do polímero catiônico tanto melhora a retenção de cargas minerais, avaliada pela turbidez do filtrado, quanto melhora a drenagem do sistema, avaliada pela velocidade de escoamento. Entretanto, elevadas dosagens deste polímero comprometeram os resultados destes parâmetros devido à inversão de carga do sistema. Pode também ser confirmado que forças de cisalhamento excessivas prejudicam a retenção de cargas minerais. Ademais, um polianfótero, com peso molecular e densidade de carga elevados, contendo grupos positivo (N-[3-(N,N-dimetilamino)propil]acrilamida), negativo (ácido metileno butanodióico) e nulo (acrilamida) na mesma cadeia, foi testado como agente de resistência a seco do papel. Todos os estudos em nível molecular sobre o comportamento do polianfótero em solução e o seu comportamento de adsorção sobre superfícies modelos carregadas, em diferentes condições de pH e de força iônica, foram importantes para explicar tanto dos fenômenos de adsorção, envolvendo fibras celulósicas e polianfótero, quanto o seu efeito na resistência mecânica do papel. Foi observado que a solubilidade do polímero aumenta à medida que o pH se distancia do seu ponto isoelétrico, pHPIE 7,3, e reduz para valores de pH próximos ao pHPIE. O tamanho das estruturas do polianfótero depende do pH do meio de dispersão. As características de tamanho do polianfótero tanto sob a forma de cadeias individuais ou quanto sob a forma de agregados, foram medidas através da técnica de espalhamento dinâmico de luz. As propriedades viscoelásticas das camadas adsorvidas e a quantidade de polímero adsorvida foram medidas através da técnica da balança microgravimétrica com dissipação de energia. Estas duas determinações, associadas às imagens no microscópio de força atômica, foram importantes para o entendimento dos resultados práticos do uso do polianfótero como agente de resistência a seco do papel. Maiores resultados de resistência do papel, avaliada através da resistência à tração, foram alcançados para valores de pH próximos ao ponto isoelétrico onde foram encontrados o seguinte: (1) maiores tamanhos para as estruturas do polímero em solução, (2) maior quantidade de massa nas camadas adsorvidas e (3) a formação de camadas mais viscoelásticas. O fenômeno de separação de fases, associado à mudança da solubilidade do polímero em solução devido ao balanço dos grupos positivos e negativos ionizados ao longo da faixa de pH estudada, foi considerado o principal aspecto para a variação em tamanho dos agregados. Embora este polímero tenha apresentado comportamento antipolieletrólito devido à expansão da sua cadeia e ao aumento da densidade de carga com o aumento da força iônica, considerando o efeito da força iônica para pH 4,3, o comportamento de adsorção do polianfótero foi avaliado como o comportamento de um polieletrólito monocarregado de alta densidade de carga. Maiores e menores quantidades de massas adsorvidas foram encontradas para valores intermediários e extremos de força iônica, respectivamente. As interações eletrostáticas foram consideradas as principais responsáveis pela adsorção do polímero sobre superfícies carregadas. Entretanto, a blindagem de cargas foi considerada a explicação para os baixos valores de massa adsorvida para valores mais elevados de força iônica.A cationic polyelectrolyte (polyamine), with low molecular weight and high charge density, usually applied as anionic trash coagulant, was used for the retention and drainage studies in the papermaking. The use of sodium carboxymethyl cellulose to simulate the anionic trash content and its effect on the filler retention was an important feature of the work. It could be noted that the increasing of the cationic polymer dosage improves both the filler retention, evaluated by the turbidity of the filtrate, and the system drainage, evaluated by the flow speed. However, high dosages of this polymer compromised the results of these parameters due to the reversal of the system charge. It can also be confirmed that excessive shear forces affect the filler retention. Furthermore, a polyampholyte, with high molecular weight and charge density, containing positive (N-[3-(N,N- dimethylamino)propyl]acrylamide), negative (methylene butanedioic acid), and neutral (acrylamide) groups in the same chain, was tested as a dry strength agent. All of the studies at molecular level concerning to the polyampholyte behavior in the solution and its adsorption behavior on charged model surfaces at different conditions of pH and ionic strength, were important to explain both the adsorption phenomena, involving cellulosic fibers and polyampholyte, and its impact on the paper strength. It was observed that the polymer solubility increases as the pH moves away from its isoelectric point, pHIEP 7.3, and decreases when the pH approaches close to pHIEP. The sizes of the structures of the polyampholytes depend on the pH of the dispersion medium. Also the size characteristics of polyampholyte, both in individual and aggregated forms, were measured by dynamic light scattering technique. The viscoelastic properties of adsorbed layers, as well as the amount of the adsorbed polymer, were measured by quartz crystal microbalance technique with energy dissipation. These two measurements, associated with the atomic force microscopy images, were important to understand the practical results of polyampholyte usage as a dry strength agent. Best results of paper strength, evaluated by paper strength index, were achieved at pH close to the isoelectric point on which one were found the following features: (1) larger sizes of the polymer structures in solution, (2) higher amount of mass in the adsorbed layers, and (3) the formation of more viscoelastic layers. The phase separation phenomenon, associated with the change in the solubility of the polymer due to the balance of the positive and negative groups throughout the studied pH range, was considered the main aspect for the variation in size of the aggregates. Although this polymer shows antipolyelectrolyte behavior due to the expansion of the its chain and the increasing in charge density with the ionic strength, considering the effect of ionic strength at pH 4.3, the adsorption behavior of polyampholyte was evaluated as a monocharged polyelectrolyte behavior with high charge density. Major and minor amounts of adsorbed masses were found for intermediates and extremes values of ionic strength, respectively. The electrostatic interactions were considered the main cause of the adsorption on charged surfaces. However, the electrostatic screening was considered the explanation for the low values of adsorbed mass at higher values of ionic strength.
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CHANG, CHE-YU, and 張哲毓. "Discussion on Regional Drainage Regulation Strategy of Okayama Air Force Airport." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/8q5uk7.
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碩士高苑科技大學
土木工程研究所
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Kaohsiung City, "Okayama Air Force Airport," the southeast region of the drainage into the lake and the bottom of the lake and other snail Lake neighborhood, because the region is a low-lying area of Okayama location for many years for showers, rain or Dianbaoxi tidal water flooding that caused the Regional water. To explore whether to use the "South-North Water Diversion" as a drainage strategy in the airport to cut the lowland runoff on the south side of the airport to the north side of Yu Kung River to improve the water problem in the airport and alleviate the drainage load in the south- , Explore the feasibility of the program as follows: First, the south side of the airport and the west side of the drainage area Liu Lo drainage drainage area of Liu Causeway to the north side of the closure of a public store outlet drainage area. Second, the airport east side of the tail discharge area of part of the runoff to the northwest side of the Yancheng drainage area exports to discharge to the public store Creek.
Books on the topic "Drainage forcé"
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Steffen Robertson and Kirsten (B. Draft acid rock drainage technical guide: Volume II, British Columbia Acid Mine Drainage Task Force report. Vancouver, B.C: Environment Canada, 1990.
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British Columbia Acid Mine Drainage Task Force., ed. Annual report: British Columbia Acid Mine Drainage Task Force. 1989/1990-. Victoria, B.C: British Columbia Acid Mine Drainage Task Force, 1990.
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West Virginia Surface Mine Drainage Task Force Symposium (14th 1993 Morgantown, West Virginia). Proceedings, fourteenth annual West Virginia Surface Mine Drainage Task Force Symposium, Morgantown, West Virginia, April 27-28, 1993. Morgantown, WV: West Virginia Surface Mine Drainage Task Force, 1993.
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West Virginia Surface Mine Drainage Task Force Symposium (16th 1995 Morgantown, West Virginia). Proceedings, sixteenth annual West Virginia Surface Mine Drainage Task Force Symposium, Morgantown, West Virginia, April 4-5, 1995. Morgantown, WV: West Virginia Surface Mine Drainage Task Force, 1995.
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United States. General Accounting Office., ed. Protest Of Air Force Contract Award For Drainage System Installation... B-277676, 159277... U.S. GAO... September 3, 1997. [S.l: s.n., 1998.
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United States. General Accounting Office., ed. PROTEST OF AIR FORCE CONTRACT AWARD FOR PARKING LOT CONSTRUCTION AND HANGAR DRAINAGE ... B-270162, 156168... U.S. GAO. [S.l: s.n., 1997.
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Commons, Canada Parliament House of. Bill: An act to continue in force the provisions of divers acts relating to "La Banque du Peuple". Ottawa: I.B. Taylor, 2002.
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Canada. Parliament. House of Commons. Bill: An act respecting the members of the North-West Mounted Police Force on active service in South Africa. Ottawa: S.E. Dawson, 2003.
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Heithaus, Evans, Almas Syed, and Chet R. Rees. Advancing the Difficult Drainage Catheter. Edited by S. Lowell Kahn, Bulent Arslan, and Abdulrahman Masrani. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199986071.003.0097.
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Advancing a drainage catheter can be difficult in certain situations, particularly when the catheter “accordions” upon itself. Most tubes are built with a small shelf in the tip of the catheter, and metal and plastic stiffeners are provided. Applying the majority of the advancing force at the hub of the metal stiffener rather than along the midportion of the catheter exerts force at the tip of the catheter via the internal metal stiffener, which is lodged against the small shelf inside the catheter. Using this method, the operator is able to translate a majority of the forward force to the catheter tip, thereby “pulling” the rest of the catheter through tissues and thus reducing the accordion effect.
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Draft acid rock drainage technical guide : British Columbia Acid Mine Drainage Task Force report. Victoria: Province of British Columbia, Ministry of Energy Mines and Petroleum Resources, 1989.
Find full textBook chapters on the topic "Drainage forcé"
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Wang, Gang. "Force Analysis and Details Design of Complex Nodes in Water Supply and Drainage Structures." In Lecture Notes in Electrical Engineering, 213–20. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-2252-9_20.
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Sperber, Daniel. "Water Supply, Sewage, and Drainage." In The City in Roman Palestine. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780195098822.003.0013.
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It is well known that Erez Yisrael was not blessed with a plentiful supply of water. Other than the narrow winding Jordan, there are few rivers in the country and hardly any fresh water lakes, other than the Sea (!) of Galilee and Huleh Lake (which virtually no longer exists). Consequently, the cities, which required an abundant and regular flow of water, relied mostly on wells and on rainwater trapped in numerous small private and public cisterns. Fountains (springs) might have been situated at considerable distances from the city, and water would have been transported via an open canal (such as in present-day Wadi Kelt between Jerusalem and Jericho), through a closed piping system, which sometimes spanned hills and valleys for many miles, or by aqueducts (such as those near Caesarea). There were also large underground water systems with vent pipes surfacing at regular intervals to relieve water and air pressure and to enable workers to inspect and clear out the silt deposits and other obstructions (witness the magnificent complex bringing water to Jerusalem through the adjacent Armon ha-Naẓiv). There were also overhead pipes made of lead, earthenware, or at times even wood that were laid out carefully above ground, taking advantage of the lay of the land and using gravitational force to transport water over a great distance from a source high in the hills to a city situated low on the plains. Such piping systems required considerable sophistication in planning and construction, not only in choosing optimal routes but also in calculating water pressures and the strengths and diameters of piping units, in placing air vents to relieve excessive pressure, and in installing sludgecocks for removing silt deposits and for filtering the water. A detailed description of different water-supply systems can be found in the work of the great first century C.E. Roman architect Vitruvius in his De Architectura.
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Romero, Leonardo, Manuel Cánovas, and Juan Sanchez-Perez. "Electroosmotic Drainage Applied to Mining Waste." In Copper - From the Mineral to the Final Application. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.106363.
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One factor affecting the stability of mining stockpiles is the moisture defined mainly by copper solution trapped in the porous by capillary. This moisture is not easy to remove if conventional methods are applied which use pressure or gravity as driving force. In the case of saturated or partially saturated soils with water, containing a large fraction of fine material, electroosmosis not only allows to reduce the humidity but also changes the structure, giving a higher strength and stability to the soils. Since the movement of the water, due to the electric gradient, is from the anode toward the cathode, the soil water content will decrease at the anode and will increase at the cathode. Water accumulated at the cathode then can be discharged by providing a drainage system at the cathode. This chapter presents theoretical and experimental aspects on electroosmotic drainage technique, based in works realized by the authors of this chapter. To explain the water flow through a mining residue containing a certain fraction of fine material and that in addition presents a high humidity, a model for the fluid flow in porous media is described here, taking into consideration two driving forces, defined by hydraulic and electric potentials.
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Oluwasegun Olamide, Fawibe, Bankole Abidemi Olalekan, Sokunbi Uthman Tobi, Mustafa Abdulwakiil Adeyemi, Joseph Oladipupo Julius, and Fawibe Kehinde Oluwaseyi. "Fundamentals of Irrigation Methods and Their Impact on Crop Production." In Irrigation and Drainage - Recent Advances [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105501.
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Water is the most precious resource on earth which is the sustenance of life. However, the competition for available water resources has intensified due to climate change and increase in global population. With a significant decrease in freshwater availability for crop production, agriculturists are open to innovation that could help save water and maximize crop production per unit drop of water. To ensure food security of a growing population, crop cultivation practices have continued to incorporate water-saving irrigation techniques to cope with water deficits, and increase crop production in an eco-friendly environment. This chapter discussed the different irrigation types based on driven-force and their specific advantages; fertigation; designing irrigation systems and scheduling of irrigation; water conservation through mulching; and water management for sustainable Integrated Pest Management (IPM). The introduction of water-saving techniques and their successful application has significantly reduced water loss through unproductive outflows and increase water and nutrients use efficiencies thereby promoting crop production. However, to achieve more success in the future, deliberate policy by government on irrigation and immense contributions from scientists would be required.
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Wang, Yong, Chao Li, Xiuquan Cao, Zuozhou Xie, and Ruizhi Pan. "Simulation and Analysis of Plunger-Type Robot’s Rubber Cylinder Structure Based on Fluid-Solid Coupling." In Advances in Transdisciplinary Engineering. IOS Press, 2023. http://dx.doi.org/10.3233/atde230139.
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The friction characteristics between the rubber cylinder and the oil tube wall significantly impact the service life and drainage performance of the plunger-type robot. This issue poses a critical technical challenge that must be addressed to promote and apply plunger robot technology. This study focuses on investigating the influence of various structural parameters of the rubber cylinder on the sealing performance of the robot cylinder. By employing a simulation approach that integrates fluid-solid coupling within the rubber cylinder structure, we examine the effects. The findings demonstrate that the rubber cylinder with W3G1.5 structural parameters exhibits more even force distribution and lower average contact friction stress.
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Galeazzo, Ludovica. "Monastic and Convent Life as a City Phenomenon." In A View of Venice, 212–25. Duke University Press, 2023. http://dx.doi.org/10.1215/9781478023807-017.
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In visual arts, historiographical writings, and literary texts, the image of the church recurs as a feature of civic identity and celebratory landmarks. Chapter 16 argues that Jacopo de’ Barbari’s View breaks with the tradition of “sacred topography” to depict monastic and convent communities as an integral part of Venetian socioeconomic life. Nearly spying beyond the impermeable spiritual walls, the artist captures the exigencies of the cenobites as well as their ties to the city. The abundance of orderly orchards, gardens, and vineyards that frame their precincts recalls these ecclesiastical spaces as fundamental food suppliers. While the range of accommodation facilities within the city’s maze—docks, boathouses, and magazines—elucidates the clergy’s involvement in everyday life activities, the strips of unsolidified soil testify to its adamant drainage activities. In the View religious life is not solely a spiritual and secluded world but a dynamic force that shapes the urban fabric.
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Evans, M. E. G. "Ground beetles and the soil: their adaptations and environmental effects." In The Environmental Impact of Burrowing Animals and Animal Burrows, 119–33. Oxford University PressOxford, 1992. http://dx.doi.org/10.1093/oso/9780198546801.003.0008.
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Abstract Ground beetles form a reservoir of predators in the upper soil levels of most terrestrial habitats. Although best known as surface runners, ground beetles may burrow into the soil to find prey, to store food such as seeds, for concealment (from predators or prey), or to reach deep hibernation sites. The most specialized burrowers are the Scaritini, which have elongate, pedunculate bodies and a range of digging adaptations. Their tunnels may reach over 70 cm, but most carabids penetrate only the more superficial layers of the soil, especially the litter and humus layers. This intrusion is facilitated by a horizontal pushing ability which differs widely between species. All carabid locomotor capabilities are compromises at various levels between the reciprocal abilities of running and pushing. Scaritines have emphasized the force component and tiger beetles the speed component, but most carabids exhibit a medium-speed/medium-force compromise. In all ground beetles the horizontal pushing ability is enhanced by a strong or weak wedge pushing ability. The ground beetle technique of wedge-pushing has been compared to the more sophisticated methods shown by two distinct groups of millipedes. The effect of all these wedge-pushers is to split up matted leaves and slow down the annual compaction of the litter layer. As with deep burrowers, their activities aid soil drainage, aeration and the movement of nutrients.
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Gurung, Anirudra, and Cyaria Gurung. "Acidophilic Microbes: Diversity and Adaptation to Low pH." In Extremophiles: Diversity, Adaptation and Applications, 105–19. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815080353122010008.
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Acidophiles are the organisms that usually grow at a pH of 3.0 or below. They usually occur in an environment rich in iron and sulfur. These organisms have the ability to oxidize sulfur and iron producing sulfuric acid thus making the environment acidic. The environments where acidophiles are commonly found are termed acid mine drainage (AMD) or acid rock drainage (ARD). The production of acid helps in the dissolution of several minerals present in the environment; hence acidophiles play important roles in bio-metallurgy. Acidophiles are a diverse group of organisms belonging to all three domains of life viz. Bacteria, Archaea to Eukarya. Many of them are obligate chemolithotrophs, and few are acidophilic heterotrophs. Usually, the chemolithotrophs are the ones that oxidize ferrous iron and sulfur into ferric iron and sulphate respectively. During their growth, they produce or secrete organic waste products, which are otherwise toxic to obligate chemolithotrophs but are usually scavenged by the acidophilic heterotrophs. Because of the acidic environment, proton concentration [H+ ] is always high outside the cell compared to the cytoplasm, thus pH gradient across the membrane is readily generated for these organisms. The pH gradient so generated forms proton motive force (PMF), which is utilized for the coupling of ADP and Pi to generate ATP molecules with the help of ATPase enzymes. However, continuous flow of proton from outside into the cell results in the cytoplasmic protonation or acidification of cytoplasm which may lead to deleterious effects such as denaturation or inactivation of several macromolecules such as DNA or proteins. Thus, the acidophiles must have evolved mechanism(s) to resist or tolerate low pH. Several mechanisms, such as proton impermeability, reverse membrane potential, etc. have been proposed to explain their ability to thrive under low pH maintaining the homeostatic balance in their systems. In this chapter, the diversity of acidophilic microorganisms and the mechanisms of their acid resistance are discussed in detail.
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Graf, William L. "The Northern Rio Grande Basin." In Plutonium and the Rio Grande. Oxford University Press, 1995. http://dx.doi.org/10.1093/oso/9780195089332.003.0008.
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In northern New Mexico, the environmental plutonium bound to sedimentary particles is the most mobile in river systems, particularly the Rio Grande. This chapter describes the physical characteristics of the drainage basin into which Los Alamos National Laboratory has released plutonium. I review those characteristics of the basin that most strongly influence the movement of sediment and its associated plutonium: landforms, geology and soils, climate, vegetation, and precipitation. Precipitation and elevation provide the energy that is the primary driving force behind river processes in the Northern Rio Grande Basin. The geographic variation in stream flow and the temporal characteristics of its magnitude and frequency explain how water, sediment, and contaminants such as plutonium move through the system. An accurate accounting of stream flow is therefore essential to the development of a basinwide budget for water, sediment, and contaminants. Calculations for the mechanics of sediment transport (and the transport of associated contaminants) thus depend on measurements of stream flow from a variety of places within the system. In this chapter I examine the basic data for stream flow in the basin and then define and explain the temporal and geographical variation in the system’s river flows. The result is a regional stream-flow budget. The portion of the Northern Rio Grande emphasized in this book consists of the watershed upstream from the U.S. Geological Survey stream gage on the Rio Grande at San Marcial, at the headwaters of Elephant Butte Reservoir. The drainage network in this 71,700-sq-km area is the principal mechanism for the surface transport and storage of plutonium. The Rio Grande begins as a trickle of meltwater from a semipermenant snowbank at Stoney Pass in the San Juan Mountains in southwestern Colorado. Steep mountain tributaries are the primary sources of water, joining the main stem as it trends southeastward to the San Luis Valley and the Alamosa, Colorado, area. Additional mountain waters from the Rio Conejos, which drains the southern San Juan Mountains in southern Colorado, join the main stream as it flows southward into New Mexico. The northern Sangre de Cristo Mountains in Colorado generate surface runoff, but relatively little reaches the main river.
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Tinker, Peter B., and Peter Nye. "Local Movement of Solutes in Soil." In Solute Movement in the Rhizosphere. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780195124927.003.0008.
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In the previous chapter, we dealt with the distribution of solutes between gas, liquid and solid phases in the soil at equilibrium; and with the rates of redistribution between these phases within soil pores. In this chapter, we consider movement of the order of 1 –1000 mm from one volume of soil to another. Such movements occur largely by diffusion and mass flow of the soil solution or soil air, and by mass movement of the body of the soil. Major movements that involve the balance and amount of solutes in the whole soil profile, including plant uptake and drainage losses, are treated in chapter 11. The process of diffusion results from the random thermal motion of ions, atoms or molecules. Consider a long column of unit cross-section orientated along the x axis, and containing a mixture of components in a single phase at constant temperature and external pressure. If the concentration of an uncharged component is greater at section A than at section B, then on average more of its molecules will move from A to B than from B to A. The net amount crossing a unit section in unit time, which is the flux, is given by the empirical relation known as Pick’s first law: . . . F = − D dC/dx (4.1) . . . where F is the flux, and dC/dx is the concentration gradient across the section. The minus sign arises because movement is from high to low concentration in the direction of increasing x. The diffusion coefficient, D, is thus defined by the equation as a coefficient between two quantities, F and dC/dx, which can be measured experimentally. It is not necessarily a constant. The diffusion coefficient of the molecules in a phase is directly proportional to their absolute mobility, u, which is the limiting velocity they attain under unit force. Terms D and u are related by the Nernst-Einstein equation: . . . D = ukT (4.2) . . . where k is the Boltzmann constant and T is the temperature on the Kelvin scale. The Nernst-Einstein equation is derived as follows (Atkins 1986, p. 675).
Conference papers on the topic "Drainage forcé"
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Fouss, James L., and Michael Sullivan. "Agricultural Drainage Management Systems Task Force (ADMSTF)." In World Environmental and Water Resources Congress 2009. Reston, VA: American Society of Civil Engineers, 2009. http://dx.doi.org/10.1061/41036(342)411.
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Richardson, Marcus Karel, and Robert Francis Kunz. "Dropwise CondensationWater Drainage Model." In 15th International Modelica Conference 2023, Aachen, October 9-11. Linköping University Electronic Press, 2023. http://dx.doi.org/10.3384/ecp204643.
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Modeling of condensation is important to estimating the residual water in small channels. The residual water that forms becomes a water source for permeable materials such as wooden structure or insulation. A model has been implemented in Modelica that will predict the amount of residual moisture after a period of water build up. This model includes parameters to relate droplet physics to a control volume. The parameters provide an macroscopic means of varying droplet adhesion force, droplet velocity, and drainage dynamics. Using CFD data as an example of real world data, this model has been correlated to demonstrate the effects of the parameters.
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Schifko, Martin, Hans Steiner, Masayasu Mohri, and Christoph Bauinger. "Enhanced E-Coating - Thickness Plus Gas Bubbles, Drainage and Buoyancy Force." In SAE 2016 World Congress and Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2016. http://dx.doi.org/10.4271/2016-01-0541.
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Buzio, R., C. Boragno, F. Buatier de Mongeot, and U. Valbusa. "Friction Force Microscopy Investigation of Elastic Instabilities in Nanolubricated Junctions." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63448.
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We present experimental results concerning the Friction Force Microscopy (FFM) investigation of smooth mica and Si surfaces lubricated by a model lubricant. We have studied the friction force as a function of normal load and sliding velocity, analyzing results in the framework of interfacial liquid structuring and drainage effects.
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Rashidi, Mohammad, Ali Ebrahimi, and Arash Mosaiebian. "Effectiveness of Subsurface Drainage for Mitigation of Landslides Affecting Pipelines." In 2022 14th International Pipeline Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/ipc2022-87107.
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Abstract Landslides can pose a threat to the integrity of new and existing pipelines if they are not mitigated. Improving subsurface drainage of groundwater is one of the most widely used stabilization strategies for mitigating landslides affecting pipelines because subsurface drainage requires minimal design and costs and can improve the overall stability. The appropriate design and implementation of this approach could lower the groundwater table within the landslide as a primary factor triggering landslide movement by reducing the driving force and increasing the shear strength or resisting force within the landslide mass. Thus, the subsurface drains are conventionally employed in the mitigation of most landslides that may threaten pipelines either as a single strategy or in conjunction with other measures. This paper presents how effective subsurface drainage systems are for improving slope stabilization in various site conditions. Included in the discussion is the predesign investigation considerations. The results of a series of two-dimensional limit equilibrium and seepage analyses are presented to evaluate the effectiveness of subsurface drainage systems. Site conditions explored in this paper include the location of the right-of-way compared to the boundary of landslide, geometry of landslide, and groundwater level. A model that uses genetic expression programming as a computational intelligence technique is introduced that predicts the effectiveness of subsurface drainage systems.
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Merritt, LaVere B., and Kevin L. Enfinger. "Tractive Force: A Key to Solids Transport in Gravity Flow Drainage Pipes." In Pipelines 2019. Reston, VA: American Society of Civil Engineers, 2019. http://dx.doi.org/10.1061/9780784482506.037.
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Talley, Matthew L., Matthew D. Zimmer, and Igor A. Bolotnov. "Coalescence Prevention Algorithm for Level Set Method." In ASME 2016 Fluids Engineering Division Summer Meeting collocated with the ASME 2016 Heat Transfer Summer Conference and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/fedsm2016-7608.
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The application of interface tracking methods to bubbly flow modeling has grown in recent years due to improvements in computing performance and development of more efficient solvers. However, the standard formulation of most interface tracking methods is not designed to physically handle the interface interactions at reasonable grid sizes. Regardless of the method used, a high grid resolution is required in the liquid film region in order to properly model drainage process during bubble interaction, which in certain conditions prevents the coalescence. This makes large scale (many bubbles) simulations unaffordable. One of the popular interface tracking approached is the level-set (LS) method. To simulate realistic bubble coalescence behavior in the LS method an algorithm with the capability of delaying or preventing the process of multiple simultaneous coalescence events has been developed. Bubble interaction plays a significant role in high void fraction flow behavior and affects the transition to other flow regimes (e.g. churn-turbulent or slug flows). The described algorithm allows to improve the accuracy of predicting coalescence events in these relevant cases and has been tested in a variety of conditions and computational meshes. This novel algorithm uses the LS method field to detect when bubbles are in close proximity, indicating a potential coalescence event, and applies a subgrid scale force to simulate the unresolved liquid drainage force. The subgrid-model is introduced by locally modifying the surface tension force near the liquid film drainage area. The algorithm can also simulate the liquid drainage time of the thin film by controlling the length of time the increased surface tension has been applied. Thus a new method of modeling bubble coalescence has been developed. Several test cases were designed to demonstrate the capabilities of the algorithm. The simulations, including a mesh study, confirmed the abilities to identify and prevent coalescence as well as implement the time tracking portion, with an additional 10–25% computational cost. Ongoing tests aim to verify the algorithm’s functionality for simulations with different flow conditions, a ranging number of bubbles, and both structured and unstructured computational mesh types. Specifically, a bubble rising towards a free surface provides a test of performance and demonstrates the ability to consistently prevent coalescence. In addition, a two bubble case and a seven bubble case provide a more complex demonstration of how the algorithm performs for larger simulations. These cases are compared to much more expensive simulations capable of resolving the liquid film drainage (through very high local mesh resolution), to investigate how the algorithm replicates the liquid film drainage process.
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Xu, Guowen, Chuan He, Chun Qi, Zheng Zhang, and Chong Dai. "Study on Water Pressure Distribution and Inner Force of Drainaged Segment Lining." In International Conference on Pipelines and Trenchless Technology. Reston, VA: American Society of Civil Engineers, 2012. http://dx.doi.org/10.1061/9780784412619.153.
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Cayer-Barrioz, J., A. Tonck, D. Mazuyer, and E. Yamaguchi. "Drainage of a Wetting Liquid: Slip Effect or Molecularly Organised Layers?" In ASME/STLE 2007 International Joint Tribology Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ijtc2007-44273.
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A Surface Force Apparatus has been used to investigate the drainage of a blend of copolymer viscosity improver additive molecules in a base oil. A quasi-static squeeze of the interface is used to characterize the first repulsion layer and the confined adsorbed layer. Moreover, dynamical measurements enlighten a significant negative value of the immobile layer thickness (−50 nm). The occurrence of slip at the wall that may result in such effect, is discussed in terms of liquid-solid interface wettability, surface roughness and cleanliness, and friction experiments. As a consequence, a modeling of the interface consisting of two layers of different viscosity is proposed. This model of interfacial molecular organization allows us to explain the drainage behaviour of the wetting liquid.
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Asmatulu, R. "Design of an Air Pressure-Assisted Centrifugal Dewatering Method for Fine Particle Suspensions." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62753.
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An air pressure-assisted centrifugal dewatering unit was designed and fabricated for the dewatering of fine particles (−150 μm), such as clay, silica, and talc. The aim of this filtration unit is to increase the filtration rate during the drainage cycle and, hence produce drier filter cakes, which in turn could reduce the cost and emission problems of thermal dryers in the preparation plants. Several dewatering parameters, including applied pressure, centrifugal force (G-force), spin time, and cake thickness were tested to optimize the processing conditions. Test results showed that at higher air pressure and centrifugal force, the cake moisture reduction was more than 60% depending on the experimental conditions. As a result, it can be concluded that the novel filtration unit effectively works on the dewatering of fine particles and can open up new opportunities in the field.
Reports on the topic "Drainage forcé"
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Curtis, Darrin L. Drainage Canal Survey, Hickam Air Force Base, Hawaii. Fort Belvoir, VA: Defense Technical Information Center, March 1993. http://dx.doi.org/10.21236/ada263478.
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