液体亚燃燃烧室点火装置工作特性数值研究

基于气体动力学和计算流体力学的相关理论,采用CFD-ACE＋流场计算软件,对液体亚燃燃烧室点火装置单独工作时的稳态流场进行了数值模拟.在试验验证的基础上分析了点火器室压、点火导管内径和导管的结构形式对火焰点火性能的影响.结果表明：当点火器室温和燃气流量恒定时,若保持管道的扩张比不变,选用较低室压的点火器更利于点火;在一定范围内增大导管内径可以提高火焰的点火性能;燃气在直管内的流动损失较小,出口射流的速度较高,穿透深度较大,带弯头的点火导管出口火焰特征类似,有无弯头对火焰的影响很大,而角度差异产生的影响很小.

Numerical study on igniter performance of liquid ramjet combustor

Based on gas dynamics and computational fluid mechanics, the numerical simulation of the steady-state flow field of igniter working independently in the liquid ramjet combustor was con-ducted with CFD-ACE＋ software. Influences of chamber pressure in igniter, ignition gas flow pipe＇s inner diameter and its structure on the flame ignition performance were analyzed on the basis of test validation. The analyzed result shows： under the conditions of constant igniter temperature and gas flow rate, lower chamber pressure in igniter is more beneficial to ignition if pipe expansion ratio re- mains unchanged; if the pipe inner diameter is increased within limits, the ignition performance of flame can be improved; if gas flows through the straight pipe it has less flow loss; the higher the gas jet flow velocity at the outlet is, the bigger the penetration depth appears; the elbow in the pipe has more influence on flame property, but the elbow angle has less influence.