临近空间飞行器再入滑移区气动热数值模拟

Numerical Study on Aerothermodynamic of Near-space Aircraft Reentry Slip-regime

计算流体力学方法(CFD)模拟滑移流区高超声速气动热时误差较大,直接蒙特卡罗模拟方法(DSMC)耗费计算资源。考虑速度滑移和温度跳跃,采用带滑移条件的CFD方法对钝头双锥体绕流进行计算分析。采用添加2阶滑移条件的N-S方程,模拟双锥绕流气动热,并与DSMC结果和文献数据进行对比分析。结果表明:滑移条件使壁面热流分布更接近DSMC模拟值,并且在克努森数不太大的过渡流区仍保持较好适用性;在克努森数较大时,带滑移条件的CFD方法模拟的流场结构存在一定误差。

As the computing error becomes bigger in slip regime while using the computational fluid dynamics method(CFD),and the direct simulation Monte Carlo method(DSMC)costs a lot of resources,velocity slip and temperature jump are considered to calculate the biconic flow by CFD method with slip condition.The Navier-Stokes(N-S)equations based on second-order slip conditions,simulate the biconic flow aerothermodynamics,the results were compared with the DSMC method and document data.Result shows that the slip condition makes the wall heat flux is nearer to DSMC simulation value,even in transition regime with low Knudsen number.Besides,the flow field structure which simulated by CFD with high Knudsen number and slip condition has error.