燃气源控制气流热效应数值模拟研究

为了解迷宫形导热套环与流体之间的热交换对控制气流温度及压力的影响,采用整体求解法求解控制气流与多层套环之间的耦合传热问题。为确保计算结果在物理上的真实性,采用“假密度法”求解以温度T为求解变量的能量方程。计算得到了控制气流参量随时间的变化情况以及迷宫形多层导热套环的温度在不同时间点的分布情况,结果表明流场的三维复杂结构使得每个小孔射流与各层套环的传热情况都不同,流体与固体区域之间的换热量随时间变化,其中内套环和中套环对流体的吸热量随时间的增长而急速下降,从而导致控制气体的温度和压力都随时间而逐渐增大。计算所得的控制气流温度和压力与试验测量值的变化趋势相同,验证了计算方法的有效性。

Numerical Study on the Effect of Heat Transfer on the Control Flow of Hot Gas Generator

The conjugate heat transfer problem between control flow and multi-layer lantern-rings was solved using unitary computation approach for understanding the influence acted on pressure and temperature of control flow by transient conjugate heat transfer. The energy equations were written into the form with temperature as the dependent variable and solved using `pseudo-density' approach to ensure the physical realism of the computed results. Flow parameters distribution of the control flow field and temperature distribution of multi-layer lantern-rings at every time step were obtained. It is indicated that heat transfer between every small orifice impinging jet and lantern-|rings was different from each other because of the special configuration and the interaction of orifice impinging jets, and because of the different quantity of heat flux between the flow and the multi-|layer lantern-|rings at every time step, especially the quantity of decalescence of the inner lantern-|ring and the middle lantern-|ring from the flow descending rapidly along with the increasing of time, the flow temperature and pressure both increased gradually along with time. The trends of changing of the numerical results were in agreement with experimental data, which illustrate the effectiveness of the methods.