运载火箭推进剂复杂流动传热问题数值模拟中的模型简化方法

在运载火箭改进优化或新型运载火箭设计过程中,会遇到各种复杂的流动与传热问题。按照真实产品和物理过程直接建立的数值计算模型过于复杂,不同尺度的结构、流动与传热、长时间的飞行过程相互耦合,出现计算时间太长(数年)、收敛困难、程序调试困难等问题。针对初始条件复杂、飞行过程复杂、边界条件复杂3类具体问题,总结了3种相应的模型简化方法,分别是工程经验法、极限参数法、低维近似法,为推进剂复杂流动与传热的数值模拟提供参考。

Model Simplification Method in Numerical Simulation of Complex Flow and Heat Transfer Process of Launch Vehicle Propellant

During the launch vehicle improvement or new launch vehicle design, various complex flow and heat transfer problems are encountered. The directly established numerical model is too complicated. The structure, flow and heat transfer at different special scales, long-time flight processes are coupled with each other, and the calculation time is too long (several years). The calculation convergence and debugging are difficult. In view of the complex initial conditions, complicated flight process and complex boundary conditions, three types of corresponding simplified methods are summarized, i.e. engineering empirical method, limited parameter method and low-dimensional approximation. These methods provide a reference for numerical simulation of complex flow and heat transfer in propellant tank.