层板推力室再生冷却通道的传热特性分析

Analysis of heat transfer for regenerative cooling channels of platelet thrust chamber

关键词:  液体推进剂火箭发动机  推力燃烧室  再生冷却  传热  数值仿真

Key words:  Liquid propellant rocket engine  Thrust chamber  Regenerative cooling  Heat transfer  Numerical simulation

摘要:

提出液体火箭发动机层板推力室再生冷却通道传热过程的数理模型。采用通用形式控制方程处理冷却剂紊流换热和通道材料导热的共轭传热问题 ,计算采用LVEL紊流模型 ,并考虑冷却剂 (氢 )的热物性参数随温度和压力的变化及层板材料热物性随温度的变化。结果表明 ,采用大高宽比、小气壁厚度的通道设计 ,可显著提高再生冷却能力 ,降低室壁温度和温差。采用对流换热系数和热物性为常数的简化处理会引起很大误差。

Abstract:

A physical mathematical model on the heat transfer of regeneratively cooling of liquid rocket platelet thrust chamber was derived.General form control equations dealing with conjugate heat transfer problems involving the coolant turbulent flow and heat conduction in the cooling channel materials was adopted in the model.The LVEL turbulence model was introduced in addition,the variation of the thermophysical properties of the coolant(hydrogen)and platelet material with temperature or pressure was considered.It was found that using high area ratio cooling channel and hot gas wall with smaller thickness the regeneratively cooling ability can be greatly improved,and the wall temperature and temperature difference in wall can be lowered.The simplified assumption of constant convective coefficient and thermophysical properties will lead great error.