Дисертації з теми "Air Blasts"
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Curry, Richard. "Response of plates subjected to air-blast and buried explosions." Doctoral thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/26877.
Повний текст джерелаChock, Jeffrey Mun Kong. "Review of Methods for Calculating Pressure Profiles of Explosive Air Blast and its Sample Application." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/32066.
Повний текст джерела
The code, BLAST.F, was used in conjunction with a commercial finite element code (NASTRAN) in a demonstration of method on a 30 by 30 inch aluminum 2519 quarter plate of fixed boundary conditions in hemispherical ground burst and showed good convergence with 256 elements for deflection and good agreement in equivalent stresses of a point near the blast between the 256 and 1024 element examples. Application of blasts to a hypothetical wing comprised of aluminum 7075-T6 was also conducted showing good versatility of method for using this program with other finite element models.
Master of Science
Magnusson, Johan. "Structural concrete elements subjected to air blast loading." Licentiate thesis, Stockholm : Byggvetenskap, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4441.
Повний текст джерелаIsmail, Mohamed Mohamed. "Blast wave parameter studies of fuel-air explosives." Thesis, Cranfield University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316143.
Повний текст джерелаAvasarala, Srikanti Rupa. "Blast overpressure relief using air vacated buffer medium." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54211.
Повний текст джерелаThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references (p. 85-88).
Blast waves generated by intense explosions cause damage to structures and human injury. In this thesis, a strategy is investigated for relief of blast overpressure resulting from explosions in air. The strategy is based on incorporating a layer of low pressure-low density air in between the blast wave and the target structure. Simulations of blast waves interacting with this air-vacated layer prior to arrival at a fixed wall are conducted using a Computational Fluid Dynamics (CFD) framework. Pressure histories on the wall are recorded from the simulations and used to investigate the potential benefits of vacated air layers in mitigating blast metrics such as peak reflected pressure from the wall and maximum transmitted impulse to the wall. It is observed that these metrics can be reduced by a significant amount by introducing the air-vacated buffer especially for incident overpressures of the order of a few atmospheres. This range of overpressures could be fatal to the human body which makes the concept very relevant for mitigation of human blast injuries. We establish a functional dependence of the mitigation metrics on the blast intensity, the buffer pressure and the buffer length. In addition, Riemann solutions are utilized to analyze the wave structure obtained from the blast-buffer interactions for the interaction of a uniform wave an air-depleted buffer. Exact analytical expressions are obtained for the mitigation obtained in the incident wave momentum in terms of the incident shock pressure and the characteristics of the depleted buffer. The results obtained are verified through numerical simulations.
(cont.) It is found that the numerical results are in excellent agreement with the theory. The work presented could help in the design of effective blast protective materials and systems, for example in the construction of air-vacated sandwich panels. Keywords: Blast Mitigation, Air-depleted Buffer, Low Pressure, Blast Waves, Sandwich Plates, Numerical Simulations
by Srikanti Rupa Avasarala.
S.M.
Fox, Matthew J. "Numerical modeling of air blast effects on hybrid structures." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2630.
Повний текст джерелаTitle from document title page. Document formatted into pages; contains x, 114 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 42-45).
Bigikocin, Onur. "Presplit Blast Induced Air Overpressure Investigation At Usak Kisladag Gold Mine." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608741/index.pdf.
Повний текст джерелаDavids, Sean. "The influence of charge geometry on the response of cylinders to internal air blasting." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20400.
Повний текст джерелаAhmed, Tushar. "Atomization and Combustion of Hybrid Electrohydrodynamic-Air-Assisted Sprays." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28180.
Повний текст джерелаDeng, Tian. "LES combined with statistical models of spray formation closely to air-blast atomizer." Thesis, Ecully, Ecole centrale de Lyon, 2011. http://www.theses.fr/2011ECDL0037/document.
Повний текст джерелаThis thesis introduced an extension to stochastic approach for simulation of air-blast atomization closely to injector. This approach was previously proposed in publications of Gorokhovski with his PHD students. Our extension of this approach is as follows. In the framework of LES approach, the contribution of primary atomization zone is simulated as an immersed solid body with stochastic structure. The last one is defined by stochastic simulation of position-and-curvature of interface between the liquid and the gas. As it was done previously in this approach, the simulation of the interface position was based on statistical universalities of fragmentation under scaling symmetry. Additionally to this, we simulate the outwards normal to the interface, assuming its stochastic relaxation to isotropy along with propagation of spray in the down-stream direction. In this approach, the statistics of immersed body force plays role of boundary condition for LES velocity field, as well as for production of primary blobs, which are then tracked in the Lagrangian way. In this thesis, the inter-particle collisions in the primary atomisation zone are accounted also by analogy with standard kinetic approach for the ideal gas. The closure is proposed for the statistical temperature of droplets. The approach was assessed by comparison with measurements of Hong in his PHD. The results of computation showed that predicted statistics of the velocity and of the size in the spray at different distances from the center plane, at different distances from the nozzle orifice, at different inlet conditions (different gas velocity at constant gas-to-liquid momentum ratio, different gas-to-liquid momentum ratio) are relatively close to measurements. Besides, the specific role of recirculation zone in front of the liquid core was emphasized in the flapping of the liquid core and in the droplets production
Gardner, Kevin Alexander. "Experimental Study of Air Blast and Water Shock Loading on Automotive Body Panels." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1468938824.
Повний текст джерелаEmmanuelli, Gustavo. "An Assessment of State Equations of Air for Modeling a Blast Load Simulator." Thesis, Mississippi State University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10979719.
Повний текст джерелаWhen an explosive detonates above ground, air is principally the only material involved in the transmission of shock waves that can result in damage. Hydrodynamic codes that simulate these explosions use equations of state (EOSs) for modeling the behavior of air at these high-pressure, high-velocity conditions. An investigation is made into the effect that the EOS selection for air has on the calculated overpressure-time waveforms of a blast event. Specifically, the ideal gas, Doan-Nickel, and SESAME EOSs in the SHAMRC code were used to reproduce experiments conducted at the Blast Load Simulator (BLS), a large-scale shock tube operated by the U.S. Army Engineer Research and Development Center, that consisted of subjecting an instrumented rigid box at three angles of orientation inside the BLS to a blast environment. Numerical comparisons were made against experimentally-derived confidence intervals using peak values and several error metrics, and an attempt was made to rank the EOS based on performance. Issues were noted with the duration of decay from maximum pressure to negative phase that resulted in a general underprediction of the integrated impulse regardless of EOS, while the largest errors were noted for gages on faces at 45 to 90 degrees from the initial flow direction. Although no significant differences were noticed in the pressure histories from different EOSs, the ideal gas consistently ranked last in terms of the error metrics considered and simultaneously required the least computing resources. Similarly, the Doan-Nickel EOS slightly performed better than SESAME while requiring additional wallclock time. The study showed that the Doan-Nickel and SESAME EOSs can produce blast signatures with less errors and more matches in peak pressure and impulse than the ideal gas EOS at the expense of more computational requirements.
Hadjiyiannis, Constantinos. "Investigation of break-up process of liquids and downstream spray characteristics in air-blast atomisers." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/23215.
Повний текст джерелаLa, Flèche Maxime. "Dynamics of Blast Wave and Cellular H2-Air Flame Interaction in a Hele-Shaw Cell." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38178.
Повний текст джерелаABU-NABAH, BASSAM ABDEL-JABER. "SWIRL ORIENTATION EFFECT ON THE INSTABILITY AND THE BREAKUP OF ANNULAR LIQUID SHEETS." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1060978117.
Повний текст джерелаMcBride, David Iain. "Air blast circuit breaker impulse noise : the role of audiometry in risk assessment of industrial noise." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393839.
Повний текст джерелаAmirrasouli, Benyamin. "Mechanical properties of low density fibre-reinforced cellular concrete and its energy absorption potential against air blast." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/mechanical-properties-of-low-density-fibrereinforced-cellular-concrete-and-its-energy-absorption-potential-against-air-blast(a8457a33-c479-4db9-adbc-579599783bc9).html.
Повний текст джерелаRuiz, Josue O. "Manufacturing and Instrumentation of an Open End Compressed Air Shock Tube." DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1843.
Повний текст джерелаYokomizu, Yasunobu, Toshiro Matsumura, Akiji Matsuda, and Hideyuki Ohno. "Dependence of arc interrupting capability on spatial distribution of airflow velocity in air-blast flat-type quenching chamber." IEEE, 2003. http://hdl.handle.net/2237/6793.
Повний текст джерелаSilveira, Carina Folgearini. "Extensão, gravidade e fatores associados à hipersensibilidade dentinária : estudo transversal." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/152690.
Повний текст джерелаDentin hypersensitivity (DH) is described in the literature as an acute short-term pain caused by thermal, tactile, osmotic, chemical or evaporative stimuli in the region of dentin exposure and not attributed to pain caused by the presence of defect or disease of dental origin. Therefore, the aim of this study was to evaluate the extent and severity of DH, as well as its correlation with periodontal indicators [plaque index (PI), gingival index (GI) and gingival recession (GR)] in 132 individuals with DH diagnosed by thermal/evaporative (air blast) stimulation associated with the Schiff scale. Descriptive analyzes were made and the mean percentages of PI and GI were estimated considering 6 sites per tooth and also 3 buccal sites. In addition, the data were analyzed using univariate and multivariate models using linear regression analysis. The mean age was 30.66 ± 10.33, female sex being more affected by DH (83.3%). It was possible to observe that DH was associated to gingival recession. The prevalence of teeth with gingival recession was 17.17%, while the prevalence of recession in teeth with DH was 77.1%. The mean of vestibular recession was 1.58 ± 0.87, and when considered the mean teeth with 1 or more millimeters recession, it was observed that, a mean of 4.48 teeth presented this condition. A higher mean number of teeth with recession and lower mean PI scores in the vestibular sites were associated (p<0.001) with the mean number of teeth with DH. The severity of DH in number of patients was significantly influenced by the higher mean of gingival recession and was higher in the female patients. Teeth that had higher recession mean and higher mean PI scores at the buccal sites, but lower GI scores at this sites, presented significantly higher values on the Schiff scale (p <0.05). In view of the findings, it is possible to observe that DH patients have a large number of teeth affected by this condition and that these present gingival recession. In addition, in the teeth that present DH, the severity is associated with the presence of more plaque and better gingival condition, in addition to the extent of the recession.
Venter, Sarel Jacobus, and D. G. Kroger. "The effectiveness of axial flow fans in a-frame plenums." Thesis, Stellenbosch : University of Stellenbosch, 1990. http://hdl.handle.net/10019.1/15625.
Повний текст джерела260 leaves printed single pages, preliminary pages i-xxi and numbered pages Chapter 1/1.1-1.3, Chapter 2/2.1-2.17, Chapter 3/3.1.1-3.10, Chapter 4/4.1-4.18, Chapter 5/5.1-5.3, References pages R.1-R.7, Appendix A pages A.1-A.34, Appendix B pages B.1-B.34, Appendix C pages C.1-C.26, Appendix D pages D.1-D.16, Appendix E pages E.1-E.30, Appendix F pages F.1-F.39. Includes bibliography, list of tables, figures and symbols.
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ENGLISH ABSTRACT: The ultimate goal of this project is to ensure a better understanding of the governing mechanisms present when flow distorting components are installed in close proximity of an axial flow fan. The effect of different parameters on the operation of axial flow fans is investigated. These parameters are divided into flow enhancing and flow reduction effects. The performance of an axial flow fan can be enhanced by changing the tip clearance, by adding a solid disc to the hub of the fan or by varying the number of fan blades. Flow reductions are caused by components such as inlet grids, walkways and their supporting structures, heat exchangers and windwalls. The effects of flow enhancing components are measured and compared to the results of other authors. The sensitivity of these effects to parameters such as the type of fan rotor and the specific system in which the rotor is installed is highlighted. The system effect (the interaction between the fan rotor and flow resistances in close proximity of each other) of individual components, as well as the combination of different components, is predicted both theoretically and experimentally. These predictions are compared to measured data relevant to the components in an installation where the system effects are present. The results are correlated to the kinetic energy flux coefficient of the flow at different locations within the installation. Experimental data obtained from a full scale unit (inlet shroud diameter of 9,216 m) are used to compare to scaled data from the model (inlet shroud diameter of 1,542 m). The hub to tip ratio of the axial flow fans investigated is 0,15. The most important conclusions are that the performance of the type of axial flow fan under investigation can be improved by reducing its tip clearance and by installing a solid disc to the downstream side of the rotor. An increase in the number of blades of the fan leads to only marginal improvements in the fan performance. The overall performance of the system can also be improved by removing some of the flow resisting components, or by changing their relative positions. All these conclusions are based on the assumption that the power input to the fan rotor remains constant.
AFRIKAANSE OPSOMMING: Die uiteindelike doel van hierdie projek is om te verseker dat die beherende meganismes wat teenwoordig is wanneer vloeiversteurende komponente in die nabyheid van 'n aksiaalwaaier geinstalleer word, beter verstaan word. Die effek van verskillende parameters op die werkverrigting van aksiaalwaaiers word ondersoek. Hierdie parameters word verdeel in vloeiverbeterings- en vloeiverminderingseffekte. Die werkverrigting van 'n aksiaalwaaier kan verbeter word deur die lempuntspeling te verstel, deur 'n soliede skyf aan die naaf van die waaierrotor te installeer, of deur die aantal lemme te verander. Die vloeiverminderings word veroorsaak deur inlaatsiwwe, loopvlakke en hul ondersteuningsstrukture, warmteruilers en windwande. Die effekte van vloeiverbeteringskomponente word gemeet en vergelyk met die resultate van ander outeurs. Die sensitiwiteit van hierdie effekte op parameters soos die tipe rotor en die spesifieke stelsel waarin die rotor geinstalleer is, word uitgelig. Die stelseleffek (die interaksie tussen die rotor van die waaier en vloei weerstande wat naby mekaar geinstalleer is) van individuele, sowel as 'n kombinasie van verskillende komponente, word teoreties en eksperimenteel voorspel. Hierdie voorspellings word dan vergelyk met eksperimentele data wat van toepassing is op die komponente in 'n installasie waar stelseleffekte voorkom. Die resultate word gekoppel aan die kinetiese energievloedkoeffisient van die vloei by verskillende posisies binne die installasie. Eksperimentele data, verkry vanaf 'n volskaaleenheid (inlaatmondstukdiameter van 9,216 m), word met die geskaleerde data van die model (inlaatmondstukdiameter van 1,542 m) vcrgelyk. Die naaf- tot hulsverhouding van die aksiaalwaaiers wat ondersoek word is 0,15. Die belangrikste gevolgtrekkings is dat die werkverrigting van die tipe aksiaalwaaier wat ondersoek word verbeter kan word deur die lempuntspeling te verminder en deur 'n soliede skyf te installeer by die stroomaf kant van die rotor. 'n Toename in die aantal lemme van die waaier lei slegs tot marginale verbeterings in die werkverrigting van die waaier. Die totale werkverrigting van die stesel kan ook verbeter word deur sommige vloeiweerstandskomponente te verwyder, of deur hulle relatiewe posisies te verander. Al hierdie gevolgtrekkings is gebasseer op die aanname dat die drywingsinset na die waaierrotor konstant bly.
Pawlowicz, Jakub. "Evaluation of air entraining behaviour in concrete using computer aided methods on hardened samples." Thesis, KTH, Betongbyggnad, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264752.
Повний текст джерелаBetongindustrins ökande medvetenhet om hållbarhet leder till att man inom dimensionering ochutförande fokuserar mot att undvika kostnadskrävande och oförutsedda underhållsåtgärder ochistället lägga större vikt på att förebygga skador i produktionens tidiga skeden. En av dessaåtgärder, som hanterar problemet frostnedbrytning, är en medveten inblandning av luftbubblor ibetongen. Mekanismen för att skapa luftporssystemet kan emellertid bli negativt påverkad underolika skeden av produktionen av många faktorer såsom cementtyp, tillsatsmedelsdos, gjutvillkoroch blandningsordning. Därför behöver man reflektera över pålitliga verktyg för utvärderingenav slutprodukten. Den experimentella studien, som presenteras i detta arbete, fokuserar motförståelse hur slagg och tillsatsmedelsdos påverkar den hårdnade betongens luftporssystem. Tretyper av cement utvärderades, dels ett normalt portlandcement, dels två typer av CEM III-cementmed olika andelar av slagg. Optimala mängder av luftporbildare och flyttillsatsmedel valdesmen reducerades senare för att undersöka deras inverkan på totalt luftinnehåll samt luftporernasavståndsfaktor och specifika yta. Den huvudsakliga metoden som valdes för denna utvärderingvar en flatbäddsscanner (kontorsmodell) för att ta bilder och användningen av en programvaravid namn BubbleCounter för att analysera luftporssystemet. Detta tillvägagångssätt baseras påanalys av tvärgående linjer och kräver en speciell behandling av ytan för att åstadkomma kontraster.Provkroppar för analysen sågades ut ur hårdnade betongkuber och polerades för att erhålla en jämnyta. Provkropparna var senare behandlade med svart bläck och zinkoxidpasta för att åstadkomma entydlig kontrast mellan de vita porerna och den svarta ytan av cementpasta och ballast. För att studeranoggrannheten hos denna metod användes som jämförelse även mer konventionella metoder sommätningar med trycksatta givare och luftporsanalys. De framtagna blandningarna visade signifikantaskillnader i luftporernas egenskaper mellan betong med normalt portlandcement och betong medslaggcement, där den senare påverkades i mindre grad av reduktioner i dosen luftporbildare.Förändringar I avståndsfaktor och specifik yta noterades också men försämringen följde inte sammamönster som den för totala luftinnehållet. Ingen signifikant skillnad mellan de två cementeninnehållande slagg kunde observeras. En intressant inverkan av det använda polykarboxylateterbaseradeflyttillsatsmedlet på luftporbildarens reaktivitet noterades. Den visade en försämringav luftporernas egenskaper vid en reduktion av mängden flyttillsatsmedel. En jämförelse avresultaten från de olika metoderna för luftporsanalys indikerade en övergripande överensstämmelsegällande de uppmätta luftporssystemens förändring p.g.a. förändringar i mängden luftporbildare.Programvaran BubbleCounter tenderade emellertid att något överskatta materialets motstånd motfrostnedbrytning med de mest optimistiska värdena för luftporernas avståndsfaktor och specifikayta.
Shittu, Kazeem Dolapo. "An investigation of the response of an FPSOV structures to external air blast : a case study of FPSOV operating in the Niger Delta." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2496.
Повний текст джерелаPumipunta, Surachai Quackenbush Stephen L. "Can money buy health? foreign aid, changes in aid, and the impact of human health in sub-Saharan Africa /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2009. http://hdl.handle.net/10355/6721.
Повний текст джерелаLopes, Claudio Rocha. "Caracteriza??o f?sica, qu?mica e energ?tica de biomassa e seus carv?es para inje??o em altos-fornos." Universidade Federal Rural do Rio de Janeiro, 2010. https://tede.ufrrj.br/jspui/handle/jspui/2247.
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The aim of this study was to characterize the main physical and chemical properties, and testing of combustion and CO2 reactivity of biomass, towards its use as material injetante the tuyeres of blast furnaces. This aims to use economic and environmental gains by reducing the rates of carbon emissions and trading of Certified Emission Reductions. The biomass studied were two types of cellulignin: cellulignin from 100% wood and 50% wood + 50% organic matter of trash- MOL, five types of waste biomass in natura: marc barley, macadamia shells, cobs corn, sugar cane bagasse and wood Eucalytus urophylla. Carbonization was carried out at three temperatures (450, 600 and 900 oC) to provide data that could determine the temperature or temperature range in which the ?in natura? biomass and cellulignin should be carbonized to obtain the best properties to use as fuel/reducer in blast furnaces. Simulation tests of injection of powdered materials in blast furnaces were performed with three different masses (200, 250 and 300mg) for setting the rate of injection, after setting the mass to be injected (250mg) studied the carbonaceous were tested to obtain rates of combustion (burning efficiency). Tests were also made of mixtures of biomass with coal of low volatile coal, showing the synergy when mixing these coals. The rates of combustion-IC is obtained from the analysis of gaseous combustion products by gas chromatography. Tests of reactivity to CO2 at three temperatures (950, 1000 and 1050 oC) in order to obtain kinetic data (apparent activation energy and frequency factor) of various coals. The continuous reaction model (Equation Mampel-1st order) was used and the kinetic values obtained from the Arrhenius plot. Correlations of various physical and chemical properties of carbonaceous study (total carbon, fixed carbon, volatile matter, alkali content, density-He, density-Hg, open porosity, total porosity and surface area) compared to the rate of combustion-IC were obtained. It was also correlated the rate of combustion-IC with the values of reactivity to CO2
O objetivo geral deste trabalho foi avaliar a viabilidade de utiliza??o de biomassas e seus carv?es atrav?s da inje??o pelas ventaneiras dos Altos-Fornos - t?cnica conhecida como Inje??o de Carv?es Pulverizados (ICP). Desta forma, diferentes biomassas e seus carv?es tiveram as suas propriedades f?sicas e qu?micas avaliadas, sendo realizados tamb?m testes de combust?o e de reatividade ao CO2. Esta utiliza??o visa ganhos ambientais e econ?micos, atrav?s da redu??o dos ?ndices de emiss?es de carbono e comercializa??o de Certificados de Emiss?es Reduzidas. As biomassas estudadas foram dois tipos de celuligninas: celuligninas provenientes de 100% madeira e celuligninas provenientes de 50% madeira + 50% mat?ria org?nica do lixo, cinco tipos de res?duos de biomassas ?in natura?: baga?o de cevada, cascas de macad?mia, sabugo de milho, baga?o de cana e madeira de Eucalyptus urophylla. Foram realizadas carboniza??es em tr?s temperaturas (450?C, 600?C e 900?C), visando obter dados que pudessem determinar a temperatura ou faixa de temperatura na qual as celuligninas e biomassas ?in natura? devem ser carbonizadas para se obter as melhores propriedades visando a utiliza??o como combust?veis/redutor nos Altos-Fornos. Os carbon?ceos estudados foram ensaiados para a obten??o dos ?ndices de combust?o (efici?ncia de queima). Tamb?m foram realizados testes de misturas de carv?es de biomassas com carv?o mineral baixo vol?til, mostrando a sinergia quando se misturam estes carv?es. Foram realizados ensaios de reatividade ao CO2 em tr?s temperaturas (950?C, 1000?C e 1050?C) com o intuito de obter dados cin?ticos (energia de ativa??o aparente e fator de frequ?ncia) de diversos carv?es. Utilizouse o modelo de rea??o cont?nua (Equa??o de Mampel-1? ordem) e os valores cin?ticos foram obtidos atrav?s do gr?fico de Arrhenius. Correla??es de diversas propriedades f?sicas e qu?micas dos carbon?ceos estudados em rela??o ao ?ndice de combust?o-IC foram obtidas. Tamb?m foi correlacionado o ?ndice de combust?o-IC com os valores de reatividade ao CO2. Os resultados mostraram que as celuligninas CCC3(50% madeira + 50 % lixo) e CCC5 (100% madeira) possuem caracter?sticas semelhantes ao carv?o vegetal tradicional, podendo serem injetadas nas ventaneiras, sem necessidade de carboniza??o. A temperatura de carboniza??o de biomassas deve ser entre 450?C e 600?C, possibilitando melhores rendimentos gravim?tricos e boas caracter?sticas f?sico-qu?micas. De modo geral, os maiores ?ndices de combust?o foram obtidos pelos carv?es carbonizados ? 600?C e pelo Carv?o vegetal tradicional (madeira de Eucalyptus). Avaliando-se as propriedades f?sicas e qu?micas dos materiais carbon?ceos com o ?ndice de combust?o, pode-se dividir os materiais em quatro grupos espec?ficos (grupo de biomassas in natura, grupo das celuligninas, grupo dos carv?es vegetais e grupo dos carv?es minerais). Os valores dos ensaios de reatividade ao CO2 est?o em conson?ncia com os resultados de ?ndice de combust?o, onde os carv?es de celulignina, bem como os carv?es de biomassa tradicional, s?o materiais de alta reatividade com grande potencial para utiliza??o na inje??o em altoforno.
Xiao, Weifang [Verfasser], Norbert [Akademischer Betreuer] Gebbeken, Norbert [Gutachter] Gebbeken, and Hong [Gutachter] Hao. "Experimental and Numerical Investigations on the Effectiveness of Protective Barriers against Air Blast / Weifang Xiao ; Gutachter: Norbert Gebbeken, Hong Hao ; Akademischer Betreuer: Norbert Gebbeken ; Universität der Bundeswehr München, Fakultät für Bauingenieurwesen und Umweltwissenschaften." Neubiberg : Universitätsbibliothek der Universität der Bundeswehr München, 2019. http://d-nb.info/1186723874/34.
Повний текст джерелаBacharoudis, Evangelos. "Etude expérimentale et théorique du début de l'atomisation des films liquides cisaillés horizontaux en présence d'un changement brusque de géométrie : application aux essuie-glaces." Thesis, Valenciennes, 2012. http://www.theses.fr/2012VALE0029/document.
Повний текст джерелаDriving the car in hazard conditions, like an environment with a lot of dust, is a case which is encountered often by the drivers. The wiper blades have to work successfully and clean the dirty windshield for both the safety of the passengers and the functionality of the car. Activating the car nozzle jets, washer is ejected from the nozzles towards the wiper blades and the windshield. A thin layer of liquid is developed on the surfaces of the wiper blades. When the nozzle jets stop and the wiper blades continue to move, the thin layer of liquid interacts with the strong external air flow field. The result of the interaction is the generation of droplets which are transported by the air flow far from the wiper blades. However, a part of those droplets impact on the windshield resulting in an insufficient cleaning of the screen and the deterioration of the driver’s sight. The wiper blades may remove the dust from the screen but they will cause the droplet impact on it. The phenomenon of the air-liquid interaction on the wiper blades involving the droplet generation, transport and impact on the screen is known as Overspray in the automotive domain. The Overspray is an important parameter for the design and development of the wiper blades. Although Overspray has been observed quite early, little is known for the mechanisms involved in. Thus, the wiper blades still suffer to clean the windshield adequately in such conditions. The current thesis aims to give a deep insight in the Overspray focusing more on the air-liquid interactions for the droplet generation, especially, the investigation of the critical conditions for the onset of the film atomization from the blade surfaces. For that reason mainly experimental and theoretical work has been conducted
Šenovský, Petr. "Parní kotel s přihříváním páry na spalování vysokopecního plynu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231184.
Повний текст джерелаDohnal, Jakub. "Kotel na spoluspalovaní vysokopecního plynu a koksárenského plynu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-242878.
Повний текст джерелаTyagi, P. K. "Linear Instability Of Laterally Strained Constant Pressure Boundary Layer Flows." Thesis, Indian Institute of Science, 2001. https://etd.iisc.ac.in/handle/2005/265.
Повний текст джерелаTyagi, P. K. "Linear Instability Of Laterally Strained Constant Pressure Boundary Layer Flows." Thesis, Indian Institute of Science, 2001. http://hdl.handle.net/2005/265.
Повний текст джерелаMachara, Radek. "Návrh kotle na spoluspalování vysokopecního plynu a koksárenského plynu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-319265.
Повний текст джерелаBedon, Chiara. "Problemi di stabilità negli elementi in vetro strutturale e studio innovativo di facciate in vetro-acciaio sottoposte a carico da esplosione." Doctoral thesis, Università degli studi di Trieste, 2012. http://hdl.handle.net/10077/7403.
Повний текст джерелаRecentemente, la richiesta architettonica sempre più spinta di trasparenza e luminosità ha favorito la diffusione nell’edilizia del vetro come materiale da costruzione. Sebbene si tratti di un materiale ancora poco conosciuto rispetto ad altri materiali convenzionali, il vetro trova, infatti, ampia applicazione nelle realizzazioni strutturali più innovative. Anche se le soluzioni architettoniche proposte trovano ampio consenso, spesso la difficoltà principale consiste nel dimensionare adeguatamente tali elementi e nel preservarne l’integrità da eventuali fenomeni di instabilità. Con riferimento a questo tema, nella presente tesi vengono proposte alcune significative formulazioni analitiche per la verifica di stabilità di elementi in vetro monolitico, stratificato o vetro-camera, con particolare attenzione per il comportamento di travi compresse, travi inflesse, pannelli sottoposti a compressione nel piano o taglio nel piano. Allo stesso tempo, viene studiato il comportamento di facciate in vetro-acciaio sottoposte a carico da esplosione, con riferimento specifico a due tipologie di facciata note come facciate continue a lastre indipendenti, controventate da un sistema di cavi pretesi, e facciate a pannelli, nelle quali le lastre di vetro sono sostenute da un telaio metallico di supporto. Per ciascuna tipologia di facciata, vengono evidenziate le criticità dovute a carichi da esplosione di varia intensità mediante opportuni modelli numerici. Inoltre, viene analizzato l’effetto di eventuali dispositivi in grado di mitigarne le componenti principali assorbendo e/o dissipando parte dell’energia d’ingresso associata all’evento esplosivo.
Recently, due to aesthetic and architectural requirements of transparency and lightness, the use of glass as a structural material showed a strong increase. Although its load carrying behavior is actually not well-known, glass finds large application in modern and innovative buildings. Nevertheless, the main difficulties are related to the proper design of these structural elements and in the preservation of their integrity, avoiding possible buckling phenomena. In this context, this Doctoral Thesis proposes a series of interesting analytical formulations suitable for the buckling verification of monolithic, laminated, insulated structural glass element, with particular attention for the load carrying behavior of beams in compression or in bending, as well as for the buckling response of glass panels subjected to in-plane compression or shear. At the same time, the Thesis focuses also on the dynamic behavior of two different typologies of steel-glass façades subjected to air blast loads, whit particular attention to the analysis of cable-supported façades and conventional curtain walls, in which a metallic frame supports the glass panels. In both the circumstances, accurate numerical simulations are performed to highlight the criticalities of similar structural systems, in presence of high-level or medium / low-level air blast loads. Finally, the structural benefits of possible devices able to mitigate the effects of explosions in the main components of these façades, by partly storing / dissipating the incoming energy, are investigated numerically and analytically.
XXIV Ciclo
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Pagani, V. "INTEGRATION OF COMPONENTS FOR THE SIMULATION OF BIOTIC AND ABIOTIC STRESSES IN MODEL-BASED YIELD FORECASTING SYSTEMS." Doctoral thesis, Università degli Studi di Milano, 2017. http://hdl.handle.net/2434/487500.
Повний текст джерелаPaleari, L. "IN SILICO IDEOTYPING: DEFINITION AND EVALUATION OF RICE IDEOTYPES IMPROVED FOR RESISTANCE/TOLERANCE TRAITS TO BIOTIC AND ABIOTIC STRESSORS UNDER CLIMATE CHANGE SCENARIOS." Doctoral thesis, Università degli Studi di Milano, 2017. http://hdl.handle.net/2434/483333.
Повний текст джерелаSamuelraj, I. Obed. "Experiments on Varying Intensity Air Blasts in Shock Tubes." Thesis, 2017. http://etd.iisc.ac.in/handle/2005/4251.
Повний текст джерелаBallantyne, Graeme. "Air-blast effects on structural shapes." 2007. http://proquest.umi.com/pqdweb?did=1397912771&sid=7&Fmt=2&clientId=39334&RQT=309&VName=PQD.
Повний текст джерелаTitle from PDF title page (viewed on Feb. 14, 2008) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Whittaker, Andrew. Includes bibliographical references.
Thom, Christopher. "Soft Materials under Air Blast Loading and Their Effect on Primary Blast Injury." Thesis, 2009. http://hdl.handle.net/10012/4861.
Повний текст джерелаLi, Larry Kin Bong. "An experimental study on air-blast atomization of viscoelastic liquids." Thesis, 2006. http://hdl.handle.net/2429/18309.
Повний текст джерелаApplied Science, Faculty of
Mechanical Engineering, Department of
Graduate
Huang, Chi-Fong, and 黃基峰. "Study on Air-cooled Blast Furnace Slag Used for Pervious Concrete." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/75562026721968897095.
Повний текст джерела國立屏東科技大學
土木工程系所
102
This study used China Steel Corporation (CSC) byproduced air-cooled blast furnace slag as aggregate material in the making of pervious concrete. The pervious concrete specimens were built according to respective water-cement ratios W/C ranged from 0.37 to 0.49, whilst aggregate particle size was between 4.8~19.1 mm. Tamping tools were two steel rods, one with 5 cm diameter round bottom, 2 cm thickness and the other with 5×5 cm square bottom, 2 cm thickness, were used to impact cylindrical and beam specimens respectively. The specimens were made by the same degree of impacting, and were performed the compressive strength, flexural strength, permeability coefficient, and porosity tests. Hopefully, the W/C of maximum strength concrete was found, and the requirements of permeability and water retention were satisfied as well. Test results showed that, both the 28 day maximum compressive strength fc and maximum modulus of rupture R occurred at W/C=0.48. The values were fc=171.4kgf/cm2 and R=41.1kgf/cm2. The mix for this specific W/C was 350 kg cement, 160 kg water, 3.5 kg curing agent and 1375 kg slag aggregate. The ratio of the 28 day compressive strength to modulus of rupture R/fc were between 0.18~0.27, averaged at 0.22, higher than that of normal concrete about 0.15. The permeability coefficient k values ranged between 0.66~2.41 cm/sec, larger than the criteria value 0.01 cm/sec proposed by Architecture and Building Research. The n values ranged between 18.5%~32.5%, also larger than the criteria value 15%.
Jyun-YanWu and 吳俊諺. "Failure Analysis of the Reinforced Concrete Plate Subjected to Air Blast Loading." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/51019497936828577088.
Повний текст джерела國立成功大學
土木工程學系碩博士班
98
Blast can cause serious damage to building structure as well as heavy loss of live and property. It is increasingly necessary and in fact required to carry out extensive research in this field when increased terrorism and local conflicts become worse. The terrorist explosion activities are increasingly concerns which could harm the national security and the social stability. The blast effect on buildings is of widely interest to researchers and engineers all over the world. Accordingly, this study to the nonlinear finite element software LS-DYNA, by select adequacy the material parameters and equation of state (EOS) to perform numerical computation related to the explosive detonates in free air. And then to examine the dynamic characteristics of the reinforced concrete structures. The results of this study provide a valuable reference for engineering designers and researchers to precede the structural dynamic analysis.
Alexander, Nicholas Anthony. "Controlled recirculation of mine ventilation air: its effect on blast contaminant dissipation." Thesis, 2014. http://hdl.handle.net/10539/15528.
Повний текст джерелаYAW, HWA LEOU, and 柳耀華. "Vibration Analysis of Rotating Blades Subjected to Sinusoidal Air Loading." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/45645977521840035731.
Повний текст джерелаLiu, Yang. "Linear and nonlinear analysis of a clamped plate subjected to air-blast loading." 2007. http://hdl.handle.net/1993/20550.
Повний текст джерелаLin, Shih-Jie, and 林士傑. "Numerical Simulation and Analysis of Methanol Atomization and Reforming Employing an Air-blast Atomizer." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/12071070202633293685.
Повний текст джерела國立成功大學
航空太空工程學系碩博士班
97
A numerical simulation model for the analysis of methanol reformers is developed in the present study. It has been applied to the analysis of two cylindrical methanol reformers. One is an isothermal methanol reformer, employing the catalyst of Cu/ZnO, the other is an auto-thermal reformer with the catalyst of Pt/CeO_2-ZrO_2. The methanol conversion and the hydrogen generation rates are predicted by the present simulation model in good agreement with the experiments. It has also been found that for the isothermal methanol reformer, increasing the space velocity and the thermal conductivity of the catalyst enhances the conversion of methanol. For the auto-thermal reformer, it is found that the reaction rate of the partial oxidation is relatively lower than those of the methanol decomposition and the water-gas shift reaction. In the present study, it is also found that the trends of the temperature distribution and the methanol conversion rate are consistent with the experimental results. The present study further analyzes an ATR reactor installed with an air-blast atomizer for atomizing liquid methanol. The detailed distributions of the flow field, temperature, and species concentration are predicted. It is found that both enlarging the spray angle and reducing the spray nozzle size increase the Methanol conversion rate and the reaction temperature .
Lin, Cyun-Syuan, and 林群軒. "Study on Air-cooled Blast Furnace Slag Used for Pervious Concrete of Low Cement Amount." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/94544501454923624453.
Повний текст джерела國立屏東科技大學
土木工程系所
103
The thesis used the air-cooled blast furnace (ABF) slag by China Steel Corporation (CSC) as aggregate and added the inorganic ion curing agent by Johnson Corporation in the making of pervious concrete. The water-cement ratios W/C of pervious concrete specimens ranged from 0.62 to 0.76. Aggregate particle size was between 4.75~19.0 mm. Cement amount C in the mix is 150 kg. Tamping tools were two steel rods, one with 5 cm diameter round bottom, 2 cm thickness, and the other with 5#westeur024#5 cm square bottom, 2 cm thickness, were used to impact cylindrical and beam specimens respectively. The specimens were made by the same degree of impacting, and were performed the compressive strength, flexural strength, permeability coefficient, and porosity tests. The purpose of the tests is to find the W/C of maximum strength for the concrete, which also have to meet the permeability and water retention requirements. Test results showed that, both the W/C of the maximum strength of 28 day concrete were 0.72. The values of the compressive strength fc and modulus of rupture R were 41.3 kgf/cm2 and 16.3 kgf/cm2 respectively. Compared with the values 171 kgf/cm2 and R=41.1 kgf/cm2 of C=350 kg, the strengths were its 0.24 and 0.4 time. The mix for this specific W/C was 167 kg cement, 75.2 kg water, 1.7 kg curing agent and 1484 kg slag aggregate. The ratio of the 7 day to 28 day compressive strength fc7/fc28 were between 0.63~1.09, averaged at 0.87. The ratio of modulus of rupture Rc7/Rc28 were between 0.63~1.23, averaged at 0.99, higher than 0.70 of normal concrete or 0.85 and 0.92 of C=350 kg concrete. The ratio of the 28 day compressive strength to modulus of rupture R/fc were between 0.26~0.40, averaged at 0.31, higher than 0.15 of normal concrete or 0.22 of C=350 kg concrete. All the permeability coefficient k values exceeded 2.3 cm/sec, far beyond the criteria value 0.01 cm/sec proposed by Taiwan Architecture and Building Center. The porosity n values ranged between 37%~45%, were also larger than the criteria value 15%. The strengths fc=41.3 kgf/cm2 and R=16.3 kgf/cm2 of the tested C=150kg ABF slag previous concrete can be used in class B pavement proposed by Taiwan Architecture and Building Center for load layer of 6 cm depth, and can be used in class A pavement for load layer of 10 cm depth.
Feng-YuWu and 吳?宇. "Analyses of the Start-up and Steady Reactions of Methanol Reforming Employing an Air-blast Atomizer." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/30514842681952147908.
Повний текст джерела國立成功大學
航空太空工程學系專班
98
The start-up process, methanol conversion and hydrogen production of the auto-thermal reformer (ATR) have been investigated by numerical simulation in the present study. The employed catalyst is Pt/CeO2-ZrO2. For the start-up process of the investigated ATR, the sparking plug is employed to ignite methanol, providing thermal energy and heating up the catalyst. As the catalyst meets the self-sustained condition, the sparking plug is shut down and the reforming reaction proceeds to the stable condition. The simulation results show that the start-up process of ATR takes less than 2 minutes when the methanol atomizer is employed. Under steady operation, increasing the air-inlet temperature has no effect on the conversion rate while it slightly reduces the hydrogen production. The results of simulation indicate that employing the atomizer leads to shorter start-up time than that of the case by gaseous feeding. The feasibility of heating the catalyst by spark ignition has been observed. The technique of spark ignition has significant benefit on the reduction of energy loss for the start-up process of the methanol reformer.
Argod, Vikas Belegundu Ashok D. "MPI enabled shape optimization of solid isotropic plates to mitigate the effects of air blast loading." 2009. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-3974/index.html.
Повний текст джерелаDeshpande, Sachin V. "Analysis Of Sulphur Hexafluoride Gas Blast Arc By A Mathematical Model." Thesis, 1997. https://etd.iisc.ac.in/handle/2005/1818.
Повний текст джерелаDeshpande, Sachin V. "Analysis Of Sulphur Hexafluoride Gas Blast Arc By A Mathematical Model." Thesis, 1997. http://etd.iisc.ernet.in/handle/2005/1818.
Повний текст джерела