论文部分内容阅读
针对双脉冲软隔层通道孔径对双脉冲发动机I脉冲燃烧室热防护层热环境的影响开展了数值仿真研究。对雷诺平均Navier-Strokes方程采用了双时间步LU-SGS迭代方法、AUSMPW迎风格式以及适合模拟分离流动的改进剪切应力输运(SST)湍流模型进行求解,通过保证流固耦合界面上的热流密度连续来实现耦合传热仿真。采用算例验证了算法及程序的精度和可信度。计算结果表明:I脉冲燃烧室热防护层表面的对流换热系数随软隔层通道孔径的增大而减小,最大对流换热系数平均减幅达20.3%,再附着点位置和对流换热系数最大值所在位置均向上游移动,分别平均移动24.2%和23.1%;I脉冲燃烧室热防护层表面的对流换热系数先增大后减小,且回流区内的对流换热系数相对较小,并在再附着点上游达到最大值。
Aiming at the influence of double-pulse soft-shelled tunnel aperture on the thermal environment of thermal shield in I pulse combustion chamber of a two-pulse engine, numerical simulation is carried out. The Reynolds-averaged Navier-Stokes equations are solved by a two-time LU-SGS iterative method, the AUSMPW upwind scheme, and an improved shear stress transport (SST) turbulent model suitable for simulating isolated flows. By ensuring that the heat flux Continuous density to achieve coupled heat transfer simulation. An example is used to verify the accuracy and reliability of the algorithm and program. The calculated results show that the convective heat transfer coefficient decreases with the increase of the aperture of the soft interlayer in the I-pulse combustion chamber. The maximum convective heat transfer coefficient decreases by an average of 20.3%, and the reattachment point and the convective heat transfer The maximum value of the coefficient moved upstream and moved 24.2% and 23.1% respectively on average. The convective heat transfer coefficient of the surface of thermal protection layer in I-pulse combustion chamber first increased and then decreased, and the convective heat transfer coefficient in the recirculation zone was relatively Small, and reach the maximum in the reattachment point.