Flame spread behaviors and temperature rise of fuel surface were experimentally investigated. A series of tests on aviation kerosene pool fires were conducted by using the schlieren image system, micro-thermocouple an...Flame spread behaviors and temperature rise of fuel surface were experimentally investigated. A series of tests on aviation kerosene pool fires were conducted by using the schlieren image system, micro-thermocouple and infrared thermal imager. The velocity evolutions of flame spread and surface flow under different initial fuel temperatures were discussed. The characteristics of fuel surface temperature rise were revealed, and it was found that the preheating effect of surface flow on fuel decreased with increasing initial fuel temperature.展开更多
To satisfy the needs of large-scale hydrogen combustion and explosion simulation,a method is presented to establish single-step chemistry model and transport model for fuel-air mixture.If the reaction formula for hydr...To satisfy the needs of large-scale hydrogen combustion and explosion simulation,a method is presented to establish single-step chemistry model and transport model for fuel-air mixture.If the reaction formula for hydrogen-air mixture is H2+0.5O2→H2O,the reaction rate model is ?? =1.13×10?5[H2][O2]exp(?46.37T0/T) mol(cm3 s)?1,and the transport coefficient model is ?=K/CP=ρD=7.0×10?5T 0.7 g(cm s)?1.By using current models and the reference model to simulate steady Zeldovich-von Neumann-Doering(ZND) wave and free-propagating laminar flame,it is found that the results are well agreeable.Additionally,deflagration-to-detonation transition in an obstructed channel was also simulated.The numerical results are also well consistent with the experimental results.These provide a reasonable proof for current method and new models.展开更多
The phenomena and mechanism of flame spread over oil floating on water were studied using temperature measurements made by fine thermocouples and an infrared camera,schlieren images of surface convection and video rec...The phenomena and mechanism of flame spread over oil floating on water were studied using temperature measurements made by fine thermocouples and an infrared camera,schlieren images of surface convection and video recordings of flame spread.The experimental results reveal that the floating-oil depth greatly affects the average rate of flame spread and average flame pulsation wavelength.The surface tension effect is the main cause of surface convection,which controls flame spread.Momentum loss and heat loss from forward-flowing hot oil to water play an important role in retarding flame spread for oil thicknesses less than about 8 mm.展开更多
文摘Flame spread behaviors and temperature rise of fuel surface were experimentally investigated. A series of tests on aviation kerosene pool fires were conducted by using the schlieren image system, micro-thermocouple and infrared thermal imager. The velocity evolutions of flame spread and surface flow under different initial fuel temperatures were discussed. The characteristics of fuel surface temperature rise were revealed, and it was found that the preheating effect of surface flow on fuel decreased with increasing initial fuel temperature.
基金supported by EU IIF-FP7 Project (Grant No. 909658)the National Natural Science Foundation of China (Grant No.50806071)the Fundamental Research Funds for the Central Universities of China
文摘To satisfy the needs of large-scale hydrogen combustion and explosion simulation,a method is presented to establish single-step chemistry model and transport model for fuel-air mixture.If the reaction formula for hydrogen-air mixture is H2+0.5O2→H2O,the reaction rate model is ?? =1.13×10?5[H2][O2]exp(?46.37T0/T) mol(cm3 s)?1,and the transport coefficient model is ?=K/CP=ρD=7.0×10?5T 0.7 g(cm s)?1.By using current models and the reference model to simulate steady Zeldovich-von Neumann-Doering(ZND) wave and free-propagating laminar flame,it is found that the results are well agreeable.Additionally,deflagration-to-detonation transition in an obstructed channel was also simulated.The numerical results are also well consistent with the experimental results.These provide a reasonable proof for current method and new models.
基金supported by the National Natural Science Foundation of China (51036007)
文摘The phenomena and mechanism of flame spread over oil floating on water were studied using temperature measurements made by fine thermocouples and an infrared camera,schlieren images of surface convection and video recordings of flame spread.The experimental results reveal that the floating-oil depth greatly affects the average rate of flame spread and average flame pulsation wavelength.The surface tension effect is the main cause of surface convection,which controls flame spread.Momentum loss and heat loss from forward-flowing hot oil to water play an important role in retarding flame spread for oil thicknesses less than about 8 mm.
