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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Sustainable High Filler Content Composite for Use in High-Volume Applications: Mechanical Performance, Thermal Stability, and Flammability of Value-added Coal Plastic Composite

Al-Majali, Yahya T. 23 May 2022 (has links)
No description available.
42

The Effect of Orientation on the Ignition of Solids

Morrisset, David 01 June 2020 (has links)
The ignition of a solid is an inherently complex phenomenon influenced by heat and mass transport mechanisms that are, even to this day, not understood in entirety. In order to use ignition data in meaningful engineering application, significant simplifications have been made to the theory of ignition. The most common way to classify ignition is the use of material specific parameters such as such as ignition temperature (Tig) and the critical heat flux for ignition (CHF). These parameters are determined through standardized testing of solid materials – however, the results of these tests are generally used in applications different from the environments in which these parameters were actually determined. Generally, ignition temperature and critical heat flux are used as material properties and are presented readily in sources such as the SFPE Handbook. However, these parameters are not truly material properties; each are inherently affected by the environment and orientation in which they are tests. Ignition parameters are therefore system dependent, tied to the conditions in which the parameters are determined. Previous work has demonstrated that ignition parameters (such as Tig or CHF) for the same material can vary depending on whether the sample is tested in a vertical or horizontal orientation. While the results are clear, the implications this may have on the use of ignition data remains uncertain. This work outlines the fundamental theory of ignition as well as a review of studies related to orientation. The aim of this study it to analyze the influence of sample orientation on ignition parameters. All experimental work in this study was conducted using cast black polymethyl methacrylate (PMMA or commonly referred to as acrylic). This study explores ignition parameters for PMMA in various orientations and develops a methodology through which orientation can be incorporated into existing ignition theory. An additional study was also conducted to explore the statistical significance of current flammability test methodologies. Ultimately, this study outlines the problem of the system dependency of ignition and provides commentary on the use of ignition data in engineering applications
43

Optical and Laser Spectroscopic Study of Microwave Plasma-Assisted Combustion

Wu, Wei 07 May 2016 (has links)
Nonthermal plasma-assisted combustion (PAC) has been demonstrated to be a promising potential method to enhance combustion performance and reduce the pollutant emissions. To better understand the mechanism in PAC, we have conducted a series of studies on the combustion enhancement by plasma using a home-developed PAC platform which employs a nonthermal microwave argon plasma and a suit of optical diagnostic tools including optical imaging, optical emission spectroscopy, and cavity ringdown spectroscopy. A new PAC system in which a continuous atmospheric argon microwave plasma jet is employed to enhance combustion of methane/air mixtures was reported. Reactive species in PAC were characterized in a state-resolved manner including the simultaneously measurements of OH(A) and OH(X) radicals in the PAC flames. Roles of the state-resolved OH(A) and OH(X) radicals in microwave PAC of premixed methane/air mixture were explored. It was concluded that if both OH(A) and OH(X) radicals assisted the ignition and flame stabilization processes, then we may hypothesize that the role of OH(A) was more dominant in the ignition enhancement but the role of OH(X) was more dominant in the flame stabilization. The effect of fuel injection configurations was investigated in the comparative study between PAC of the premixed and nonpremixed methane/air mixtures. It was found that emissions from the CH (A-X) and C2 Swan systems only exist in the nonpremixed PAC which suggest that the reaction pathways are different between premixed and nonpremixed PAC. The PAC of premixed methane/oxygen/argon mixtures was investigated. A U-shaped dual-layer curve of fuel ignition/flame stabilization limit showing the effects of the plasma power on the fuel ignition and flame stabilization was observed and reported. A parametric study of the microwave PAC of the premixed ethylene/air mixtures was conducted. Behavior of the OH, CH, and C2 radicals and their dependence on plasma power, argon flow rate, and total ethylene/air mixture flow rate were also studied.
44

Study of high flash point ethyl alcohol-based secondary fluids applied in Ground Source Heat Pumps systems

Carrion Domenech, Luis Enrique January 2019 (has links)
Ethyl alcohol (ethanol) as secondary fluids is very popular as heat transfer fluid for indirect refrigeration system with ground source heat pump systems (GSHP) in several countries such as Sweden, Norway, Switzerland, Finland and other European countries. There have been several researches about the future ofthe refrigeration sector, refrigerants and refrigeration systems. Moreover, strict regulations such as F-gasregulation and Kigali Amendment forcing a phase down of many current widely used high global warming potential (GWP) refrigerants, i.e. R134a or R410A. Therefore, secondary refrigeration systems and their working fluids are expected to play a key role in order to minimize the refrigerant charge in the systems, reduce the indirect refrigerant leakages as well as increase the safety during operation. The aim of this thesis is to investigate the effect different additives to increase the flame point together with ethanol-based secondary fluids and validate their thermophysical properties by comparing them with reference values for pure ethanol water solutions. The study aims to design a new commercial ethyl alcohol-based product for GSHP system that could replace existing ones in the Swedish market and could workwith natural or flammable low GWP refrigerants. Different high flash point additives were tested such as 1-propyl alcohol, n-butyl alcohol, glycerol andpropylene carbonate. Thermophysical properties were investigated and a GSHP model in Excel was created in order to assess the energy performance of the resulted blends. After screening different blends and assessing the energy performance, glycerol as additive in low concentration seems to be the future for the ethyl alcohol-based secondary fluids because of its high flashpoint (160ºC) that will reduce the flammability risk associated to ethyl alcohol blends, the low viscosity (by 12% lower compared to pure ethyl alcohol blends) that help reduce pumping power by 4.5% compared topure ethyl alcohol blends. Moreover, ethyl alcohol and glycerol blend showed the lost in heat transfer coefficient by 4% lower compared to pure ethyl alcohol blends due to lower thermal conductivity compared to pure ethyl alcohol blends. Finally, it is a rather cheap and natural product which has no problem related to corrosion since ethyl alcohol and glycerol are less corrosive than water. Although, flash point test was not conducted so there is no data regarding the flash point, it is expected the flash point is increased due to the high flash point of glycerol compared to ethyl alcohol or other possible additives. Therefore, it is expected that the flammability risk associated to ethyl alcohol-based secondary fluids is reduced. / Etylalkohol (etanol) som köldbärare är mycket populärt som värmeöverföringsvätska för indirekt kylsystemmed bergvärmepumpsystem (BVP) i Sverige, Norge, Schweiz, Finland och andra europeiska länder. Fleraundersökningar har gjorts om kylsektorns framtid, köldmedier och kylsystem. Dessutom strängaförordningar som F-gas förordning och Kigali- förordning tvingar en utfasning av många nuvarande allmäntanvända köldmedier med den höga globala uppvärmningspotentialen (GWP), dvs. R134a eller R410A. Därför förväntas det att kylsystem och deras köldbärare spela en nyckelroll för att minimera köldmediumsmängd i systemen, minska de indirekta köldmedieläckage och öka säkerheten under drift. Syftet med detta examensarbete är att undersöka effekten av olika tillsatser för att öka flammanpunkten tillsammans med etanolbaserade köldbärare och validera deras termofysikaliska egenskaper genom att jämföra dem med referensvärden för rena etanolvattenlösningar. Studien syftar till att utforma en nykommersiell etylalkoholbaserad produkt för BVP-system som skulle kunna ersätta befintliga produkter på den svenska marknaden och kan arbeta med naturliga eller brandfarliga köldmedier med låg GWP. Olika tillsatser med hög flampunkt testades såsom 1-propylalkohol, n-butylalkohol, glycerol och propylenkarbonat. Termofysikaliska egenskaper undersöktes och en BVP-modell i Excel skapades för att bedöma energiprestanda för olika blandningarna. De erhållna resultaten för olika blandningar visar att glycerol i en låg koncentration som tillsats kan vara framtidens additiv för de etylalkoholbaserade köldbärare på grund av dess höga flampunkt (160 ºC) som förmodligen kan minska brandrisken för etylalkoholblandningar. Dessutom hade glycerol och etanolblandningar den lägsta viskositeten (c.a.12% lägre jämfört med ren etylalkoholblandningar) som bidrar tillen minskning av pumpeffekten med c.a. 4,5% jämfört med rena etylalkoholblandningar. Däremot visade etylalkohol och glycerol blandningen c.a. 4% lägre värmeöverövergångstal jämfört med de rena etylalkoholblandningar på grund av lägre värmeledningsförmåga jämfört med ren etylalkoholblandningar. Slutligen är glycerol en ganska billig och naturlig produkt som inte har några korrosionsproblem eftersom etylalkohol och glycerol är mindre frätande än vatten. Även om flampunkttest inte genomfördes i projektet, förväntas det att flampunkten ökas lite på grund av den höga flampunkten av glycerol jämfört med etylalkohol och andra tillsatser. Därför förväntas det att brännbarhetsrisken förknippad med etylalkoholbaserade köldbärare reduceras.
45

Growth and Extinction Limits: Ground Based Testing of Solid Fuel Combustion in Low Stretch Conditions in Support of Space Flight Experiments

Johnston, Michael C. 02 February 2018 (has links)
No description available.
46

LABORATORY-SCALE EVALUATION OF ARAMID BLEND MATERIAL AS A FIRE BARRIER FOR FLEXIBLE POLYURETHANE FOAM

Shang, Wei 30 May 2016 (has links)
No description available.
47

Comparing the Ignitability of Mulch Materials for a Firewise Landscape

DeGomez, Tom, Rogstad, Alix, Schalau, Jeff, Kelly, Jack 09 1900 (has links)
5 pp. / Eight different landscape mulches were tested for their flammability using a propane torch, charcoal briquette, and a cigarette at two different times of the year. Three randomized compete blocks with eight one square meter plots were tested at three locations; Tucson, Prescott, and Flagstaff, Arizona. Each of the mulches was subjected to the heat of a handheld propane torch (15 seconds), a glowing charcoal briquette (five minutes), and a lit cigarette (until burned out). We found that the least dense mulches (pine needles and straw) burned rapidly when subjected to the torch and ignited after the briquette was removed. The medium density mulches (pine bark nuggets and wood chips) had low flame lengths and smoldered. Heavy density mulches (garden compost and shredded bark) only smoldered. The decomposed granite and sod did not ignite or smolder.
48

Análise da inflamabilidade de têxteis de uniformes de aeronautas / Analysis of textile flammability of the flight crew uniform

Silva, Marcia Cristina 06 September 2018 (has links)
As condições de inflamabilidade estabelecidas nas normas aeronáuticas aplicadas aos têxteis integrantes da cabine de passageiros do avião, não são requeridas para aplicação aos uniformes dos aeronautas. No entanto, uma vez que faz parte da função da tripulação, notadamente os comissários de voo, o combate de fogo a bordo, mesmo que esse tipo de acidente não seja frequente em relação à totalidade dos acidentes em geral desse setor, esse fato direcionou o presente estudo para conhecer os limites dos materiais têxteis dos uniformes dos aeronautas com relação à inflamabilidade. Deste modo, foram objetivos: determinar a inflamabilidade (velocidade de queima) de amostra de tecidos profissionais e de amostras de peças de uniformes de aeronautas; caracterizar os tecidos profissionais e os que constituem peças de uniformes de aeronautas, através de testes de: composição, gramatura, número de fio por trama e urdume, ligamento, espessura do tecido, diâmetro de fios, densidade linear e torção; calcular o diâmetro do fio e fator de cobertura e correlacionar os valores obtidos de inflamabilidade com os valores da caracterização dos tecidos e parâmetros calculados. Os experimentos foram realizados em três tecidos profissionais e em oito peças de uniformes de aeronautas de companhias diferentes, doadas para este estudo, além de entrevistas semiestruturadas e visita técnica. A interpretação dos resultados obtidos foi realizada com aplicação de testes de normalidade de dados, igualdade de variâncias, ANOVA, teste T e teste não paramétrico de Kruskall-Wallis. Os resultados encontrados no presente estudo não se enquadram nos limites preconizados pela FAR25 para que o material seja qualificado auto extinguível. O menor valor de inflamabilidade foi de 0,742±0,140 (cm/s). Este resultado trata-se da média obtida da velocidade de queima das 10 amostras ensaiadas do tecido da peça P7 (calça masculina) na direção da trama. A composição da peça é uma mistura de 50% lã e 50% poliéster com gramatura de 225,12±5,02 (g/m2), densidade linear do fio de 36,61±1,48 (tex) e torção de 598,00±45,34(torções/m). O diâmetro do fio calculado pelo modelo de Peirce foi de 0,219 mm. O maior valor de inflamabilidade foi 3,698±1,806 (cm/s). Este resultado trata-se da média obtida da velocidade de queima das 10 amostras ensaiadas do tecido da peça P5 (camisa masculina) na direção da trama. A composição da peça é uma mistura de 67% poliéster e 33% algodão com gramatura de 108,72±2,39 (g/m2), densidade linear do fio de 15,88±1,27 (tex) e torção de 991,00±45,75 (torções/m). O diâmetro do fio calculado pelo modelo de Peirce foi de 0,148 mm. Influência da direção na velocidade de queima. A análise de variância com todos os fatores, não foi validada pela análise dos resíduos., entretanto a verificação da relação entre as variáveis explicativas direção, material e ligamento com a variável resposta velocidade de queima realizada com o agrupamento por características físicas específicas, resultou em análises validadas por seus resíduos.Influência da direção na velocidade de queima para grupo material 100% CO, ligamento tela, a velocidade de queima é estatisticamente igual na direção de trama e urdume, grupo material 100% PES, ligamento sarja, a velocidade de queima é estatisticamente diferente, sendo menor na direção da trama, grupo material 100% PES, ligamento tela, a velocidade de queima é estatisticamente diferente, sendo menor na direção do urdume, grupo material 67% PES/33% CO, ligamento sarja e material 67% PES/33% CO, ligamento tela, a velocidade de queima é estatisticamente igual na direção de trama e urdume e grupo material 50% WO /50% PES, ligamento tela, a elocidade de queima é igual na direção de trama e urdume. Influência do material na velocidade de queima:grupo ligamento sarja, direção trama a velocidade de queima é estatisticamente diferente, sendo menor para a composição algodão (100%CO), grupo ligamento sarja, direção urdume a velocidade de queima é estatisticamente diferente, sendo menor para o material algodão (100%CO), grupo ligamento tela,direção trama a velocidade de queima é estatisticamente igual para os materiais 100%CO, 100%PES, 67%PES/33%CO e 50%WO/50%PES, grupo ligamento tela, direção urdume a velocidade de queima é estatisticamente igual para o material 67%PES/33%CO. Assim sugestões para estudos futuros podem levar em conta construções mais fechadas de tecidos; construção de tecidos com fibras de origem vegetal ou animal ou misturas com fibras sintéticas (com ou sem aditivação de retardantes de chamas) para agregação de funcionalidade; mudanças na modelagem das peças; e estudar alteração na gramatura dos tecidos e da torção dos seus fios constituintes / The flammability conditions laid down in the aeronautical standards applied to the textiles forming part of the passenger cabin of the aircraft. But these standards are not required for application to crew uniforms. However, since it is part of the function of the crew, notably flight attendants, the fire fighting on board, even if this type of accident is not frequent in relation to all accidents in general in this sector, this fact directed the present study to know the limits of the textile materials of the uniforms of the aeronauts with respect to the flammability. Thus, the objectives were: to determine the flammability (burning rate) of professional fabric samples and samples of aeronaut uniform pieces; characterize the professional fabrics and those that constitute parts of uniforms of aeronauts, through tests of: composition, weights, number of threads per weft and warp, weaving, fabric thickness, yarn diameter, linear density and torsion; calculate the yarn diameter and coverage factor and correlate the values of flammability obtained with the tissue characterization values and calculated parameters. The experiments were carried out in three professional fabrics and in eight pieces of uniforms of aeronauts from different companies donated for this study, in addition to semi-structured interviews and technical visits. The interpretation of the obtained results was carried out with application of tests of normality of data, equality of variances, ANOVA and response surface. The results found in the present study do not fit within the limits recommended by FAR25 for the material to be qualified self-extinguishing. The lowest flammability value was 0.742 ± 0.140 (cm/s). This result is the mean obtained from the burning rate of the 10 samples tested from the fabric of the P7 piece (male trousers) in the direction of the weft. The composition of the piece is a mixture of 50% wool and 50% polyester with a weight of 225.12 ± 5.02 (g/m2), linear yarn density of 36.61 ± 1.48 (tex) and a twist of 598.00 ± 45.34 (torsions/m). The yarn diameter calculated by the Peirce model was 0.219 mm. The highest flammability value was 3.698 ± 1.806 (cm/s). This result is the mean obtained from the burning rate of the 10 samples tested from the fabric of the piece P5 (male shirt) in the direction of the weft. The composition of the piece is a mixture of 67% polyester and 33% cotton with weights of 108.72 ± 2.39 (g/m2), linear yarn density of 15.88 ± 1.27 (tex) and twisting of 991.00 ± 45.75 (torsions/m). The wire diameter calculated by the Peirce model was 0.148 mm. The analysis of variance with all the factors was not validated by the residue analysis. However, the relationship between the explanatory variables \"direction\", \"material\" and \"ligament\" with the variable \"burning rate\" grouping by specific physical characteristics, resulted in analyzes validated by their residues. Influence of the \"direction\" on the \"burning rate\" for group \"material 100% CO, plain weave\", the burning speed is statistically equal in the direction of warp and weft, group \" material 100% PES, twill weave, burning rate is a statistically different one, being smaller in the direction of the weft, group \"material 100% PES, plain weave\", the burning speed is statistically different, being smaller in the direction of the warp, group \"material 67% PES / 33% CO, twill weave and \"material 67% PES / 33% CO, plain weave\", the burning speed is statistically equal in the direction of warp and warp and group \"material 50% WO / 50% PES, plain weave\", the speed of burn is equal in the direction of warp and warp. Influence of the material on the burning rate: group twill weave, direction weft burning rate is statistically different, being smaller to material 100% CO, group twill weave, direction warp burning rate is statiscally different, being smaller to material 100% CO, group plain weave, direction weft, burning rate is statiscally equal to material 100% CO, 100% PES, 67%/33%CO and 50%WO/50%PES, group plain weave, direction warp burning rate is statiscally equal to material 67%PES/33%CO. Thus suggestions for future studies may take into account more closed constructions of tissues; fabric construction with fibers of vegetable or animal origin or mixtures with synthetic fibers (with or without additives of flame retardants) for aggregation of functionality; changes in the modeling of parts; and to study alteration in the weight of the tissues and the torsion of their constituent yarns
49

Avalia??o da flamabilidade e dos res?duos de queima de tintas acr?licas ? base d'?gua

Henrique, Angelo Abel Machado Pereira 29 September 2017 (has links)
Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-06-04T14:42:13Z No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-11T14:34:47Z (GMT) No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) / Made available in DSpace on 2018-06-11T14:46:48Z (GMT). No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) Previous issue date: 2017-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In this work, the sample-flame propagation indexes were simulated in laboratory, in detriment and in comparison to the generalized burning during the fires in internal environments. The respective chemical and physical properties of the paints, the emanated gases, were compared; evidencing its toxicities, toxicological thresholds and using the tests of horizontal burning and vertical burning. In the experimental part, the paint films were produced for later burning in a quartz chamber with the use of the electric furnace, from which the gases were collected, according to each thermal degradation orientation obtained by the TGA pallet, in order to analyze the toxicities in gas chromatography. In the results the different firing behaviors for each paint can be compared by virtue of its physico-chemical composition, together with its gas release rates in each temperature range. / Neste trabalho produziu-se a partir das tintas acr?licas ? base d??gua, os ?ndices de propaga??o de chama amostral e simulada em laborat?rio, em detrimento e em comparativo ? queima generalizada durante os inc?ndios em ambientes internos. Foram comparadas as respectivas propriedades qu?micas e f?sicas das tintas, dos gases emanados; evidenciando as suas toxicidades, limiares toxicol?gicos e empregando os testes de queima horizontal e queima vertical. Na parte experimental foram produzidos os filmes de tintas, para posterior queima em c?mara de quartzo com o uso do forno el?trico, onde a partir deste, coletou-se os gases, segundo cada orienta??o de degrada??o t?rmica obtida pala TGA, para ent?o serem analisadas as toxicidades em cromatografia gasosa. Nos resultados podem ser comparados os diferentes comportamentos de queima para cada tinta em virtude de sua composi??o f?sico-qu?mica, juntamente com suas taxas de libera??es de gases em cada faixa de temperatura.
50

Análise da inflamabilidade de têxteis de uniformes de aeronautas / Analysis of textile flammability of the flight crew uniform

Marcia Cristina Silva 06 September 2018 (has links)
As condições de inflamabilidade estabelecidas nas normas aeronáuticas aplicadas aos têxteis integrantes da cabine de passageiros do avião, não são requeridas para aplicação aos uniformes dos aeronautas. No entanto, uma vez que faz parte da função da tripulação, notadamente os comissários de voo, o combate de fogo a bordo, mesmo que esse tipo de acidente não seja frequente em relação à totalidade dos acidentes em geral desse setor, esse fato direcionou o presente estudo para conhecer os limites dos materiais têxteis dos uniformes dos aeronautas com relação à inflamabilidade. Deste modo, foram objetivos: determinar a inflamabilidade (velocidade de queima) de amostra de tecidos profissionais e de amostras de peças de uniformes de aeronautas; caracterizar os tecidos profissionais e os que constituem peças de uniformes de aeronautas, através de testes de: composição, gramatura, número de fio por trama e urdume, ligamento, espessura do tecido, diâmetro de fios, densidade linear e torção; calcular o diâmetro do fio e fator de cobertura e correlacionar os valores obtidos de inflamabilidade com os valores da caracterização dos tecidos e parâmetros calculados. Os experimentos foram realizados em três tecidos profissionais e em oito peças de uniformes de aeronautas de companhias diferentes, doadas para este estudo, além de entrevistas semiestruturadas e visita técnica. A interpretação dos resultados obtidos foi realizada com aplicação de testes de normalidade de dados, igualdade de variâncias, ANOVA, teste T e teste não paramétrico de Kruskall-Wallis. Os resultados encontrados no presente estudo não se enquadram nos limites preconizados pela FAR25 para que o material seja qualificado auto extinguível. O menor valor de inflamabilidade foi de 0,742±0,140 (cm/s). Este resultado trata-se da média obtida da velocidade de queima das 10 amostras ensaiadas do tecido da peça P7 (calça masculina) na direção da trama. A composição da peça é uma mistura de 50% lã e 50% poliéster com gramatura de 225,12±5,02 (g/m2), densidade linear do fio de 36,61±1,48 (tex) e torção de 598,00±45,34(torções/m). O diâmetro do fio calculado pelo modelo de Peirce foi de 0,219 mm. O maior valor de inflamabilidade foi 3,698±1,806 (cm/s). Este resultado trata-se da média obtida da velocidade de queima das 10 amostras ensaiadas do tecido da peça P5 (camisa masculina) na direção da trama. A composição da peça é uma mistura de 67% poliéster e 33% algodão com gramatura de 108,72±2,39 (g/m2), densidade linear do fio de 15,88±1,27 (tex) e torção de 991,00±45,75 (torções/m). O diâmetro do fio calculado pelo modelo de Peirce foi de 0,148 mm. Influência da direção na velocidade de queima. A análise de variância com todos os fatores, não foi validada pela análise dos resíduos., entretanto a verificação da relação entre as variáveis explicativas direção, material e ligamento com a variável resposta velocidade de queima realizada com o agrupamento por características físicas específicas, resultou em análises validadas por seus resíduos.Influência da direção na velocidade de queima para grupo material 100% CO, ligamento tela, a velocidade de queima é estatisticamente igual na direção de trama e urdume, grupo material 100% PES, ligamento sarja, a velocidade de queima é estatisticamente diferente, sendo menor na direção da trama, grupo material 100% PES, ligamento tela, a velocidade de queima é estatisticamente diferente, sendo menor na direção do urdume, grupo material 67% PES/33% CO, ligamento sarja e material 67% PES/33% CO, ligamento tela, a velocidade de queima é estatisticamente igual na direção de trama e urdume e grupo material 50% WO /50% PES, ligamento tela, a elocidade de queima é igual na direção de trama e urdume. Influência do material na velocidade de queima:grupo ligamento sarja, direção trama a velocidade de queima é estatisticamente diferente, sendo menor para a composição algodão (100%CO), grupo ligamento sarja, direção urdume a velocidade de queima é estatisticamente diferente, sendo menor para o material algodão (100%CO), grupo ligamento tela,direção trama a velocidade de queima é estatisticamente igual para os materiais 100%CO, 100%PES, 67%PES/33%CO e 50%WO/50%PES, grupo ligamento tela, direção urdume a velocidade de queima é estatisticamente igual para o material 67%PES/33%CO. Assim sugestões para estudos futuros podem levar em conta construções mais fechadas de tecidos; construção de tecidos com fibras de origem vegetal ou animal ou misturas com fibras sintéticas (com ou sem aditivação de retardantes de chamas) para agregação de funcionalidade; mudanças na modelagem das peças; e estudar alteração na gramatura dos tecidos e da torção dos seus fios constituintes / The flammability conditions laid down in the aeronautical standards applied to the textiles forming part of the passenger cabin of the aircraft. But these standards are not required for application to crew uniforms. However, since it is part of the function of the crew, notably flight attendants, the fire fighting on board, even if this type of accident is not frequent in relation to all accidents in general in this sector, this fact directed the present study to know the limits of the textile materials of the uniforms of the aeronauts with respect to the flammability. Thus, the objectives were: to determine the flammability (burning rate) of professional fabric samples and samples of aeronaut uniform pieces; characterize the professional fabrics and those that constitute parts of uniforms of aeronauts, through tests of: composition, weights, number of threads per weft and warp, weaving, fabric thickness, yarn diameter, linear density and torsion; calculate the yarn diameter and coverage factor and correlate the values of flammability obtained with the tissue characterization values and calculated parameters. The experiments were carried out in three professional fabrics and in eight pieces of uniforms of aeronauts from different companies donated for this study, in addition to semi-structured interviews and technical visits. The interpretation of the obtained results was carried out with application of tests of normality of data, equality of variances, ANOVA and response surface. The results found in the present study do not fit within the limits recommended by FAR25 for the material to be qualified self-extinguishing. The lowest flammability value was 0.742 ± 0.140 (cm/s). This result is the mean obtained from the burning rate of the 10 samples tested from the fabric of the P7 piece (male trousers) in the direction of the weft. The composition of the piece is a mixture of 50% wool and 50% polyester with a weight of 225.12 ± 5.02 (g/m2), linear yarn density of 36.61 ± 1.48 (tex) and a twist of 598.00 ± 45.34 (torsions/m). The yarn diameter calculated by the Peirce model was 0.219 mm. The highest flammability value was 3.698 ± 1.806 (cm/s). This result is the mean obtained from the burning rate of the 10 samples tested from the fabric of the piece P5 (male shirt) in the direction of the weft. The composition of the piece is a mixture of 67% polyester and 33% cotton with weights of 108.72 ± 2.39 (g/m2), linear yarn density of 15.88 ± 1.27 (tex) and twisting of 991.00 ± 45.75 (torsions/m). The wire diameter calculated by the Peirce model was 0.148 mm. The analysis of variance with all the factors was not validated by the residue analysis. However, the relationship between the explanatory variables \"direction\", \"material\" and \"ligament\" with the variable \"burning rate\" grouping by specific physical characteristics, resulted in analyzes validated by their residues. Influence of the \"direction\" on the \"burning rate\" for group \"material 100% CO, plain weave\", the burning speed is statistically equal in the direction of warp and weft, group \" material 100% PES, twill weave, burning rate is a statistically different one, being smaller in the direction of the weft, group \"material 100% PES, plain weave\", the burning speed is statistically different, being smaller in the direction of the warp, group \"material 67% PES / 33% CO, twill weave and \"material 67% PES / 33% CO, plain weave\", the burning speed is statistically equal in the direction of warp and warp and group \"material 50% WO / 50% PES, plain weave\", the speed of burn is equal in the direction of warp and warp. Influence of the material on the burning rate: group twill weave, direction weft burning rate is statistically different, being smaller to material 100% CO, group twill weave, direction warp burning rate is statiscally different, being smaller to material 100% CO, group plain weave, direction weft, burning rate is statiscally equal to material 100% CO, 100% PES, 67%/33%CO and 50%WO/50%PES, group plain weave, direction warp burning rate is statiscally equal to material 67%PES/33%CO. Thus suggestions for future studies may take into account more closed constructions of tissues; fabric construction with fibers of vegetable or animal origin or mixtures with synthetic fibers (with or without additives of flame retardants) for aggregation of functionality; changes in the modeling of parts; and to study alteration in the weight of the tissues and the torsion of their constituent yarns

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