氢氧火炬点火器低压燃烧流动仿真研究

为研究低压条件下氢氧喷注间距及液滴粒径对氢氧火炬式电点火器燃烧流动的影响规律，结合DPM离散相模型，采用6组分16步氢氧反应机理，选取考虑湍流燃烧效应的涡耗散概念燃烧模型进行仿真计算，并将结果与试验结果进行比对，温度结果符合得较好，压强计算偏差在5%以内，验证了仿真模型的准确性。仿真结果表明:低压条件下，氢氧喷注间距增加时，点火器头部内壁温度升高，室压降低，燃烧长度缩短；液氢液滴直径增大时，点火器头部内壁温度升高，室压降低，燃烧长度变长；改变液氧液滴直径对点火器燃烧流动影响较小。 

Simulation study on combustion flow in low-pressure condition of hydrogen-oxygen torch ignitor

The effects of hydrogen-oxygen injection interval and droplet mean diameter on the combustion flow of the low-temperature liquid hydrogen and liquid oxygen torch electric ignitor in low-pressure condition were investigated by numerical simulation.Discrete phase model（DPM） and 16-step，6 species hydrogen-oxygen chemical reaction mechanism were applied for the analysis.Considering the turbulent combustion effect，the eddy dissipation concept combustion model was utilized for simulation calculation.The temperature results obtained by simulation were in good agreement with those obtained by experiment，and the deviations of pressure were within 5%，thereby verifying the accuracy of the numerical models.As the results shown，under low-pressure condition，when the hydrogen-oxygen injection interval increased，the ignitor head inner wall temperature increased，the chamber pressure decreased，and the combustion length decreased.The larger liquid hydrogen droplets diameter resulted in the longer combustion length and higher head inner wall temperature，besides，the pressure in the ignitor chamber was slightly reduced.The diameter of liquid oxygen droplets had little effect on combustion flow of the ignitor.