翼柱型药柱内三维湍流流动仿真

SIMULATION OF 3-D TURBULENT FLOW IN PASSAGES OF FINOCYL GRAIN

关键词:  固体推进剂火箭发动机  喷管气流  三维流  模拟

Key words:  Solid propellant rocket engine  Nozzle gas flow  Three dimensional flow  Simulation

摘要:

应用Ｓｉｍｐｌｅ方法进行了固体火箭发动机燃烧室中的三维流动仿真。所考虑的物理因素如下：翼柱型药柱，三维加质不可压湍流，移动的燃面边界，燃气的热辐射等。方程为：三维连续、动量和能量方程，ｋ－ε湍流模型，三维热辐射通量方程等。为了处理燃面移动边界，提出了标记网格示踪技术。计算结果获得了固体火箭发动机燃烧室翼柱型药柱中三维流动的参数分布。同时，揭示了某些新现象和新规律：翼和柱通道间的几何匹配及其中的加质强度对流动参数有强烈的影响，甚至可能发生反向流动和旋涡；在一定条件下，翼通道下游附近可能产生明显的周向旋涡。

Abstract:

SIMPLE mothod is opplied to finish 3-D flow simulation in chamber of SPRM. The considered physical factors are as follows: finocyl grain, 3-D mass addition and incompressible turbulent flow, moving boundaries of propellant buring surfaces, heat radiation of gas, and so on. Equations are: 3-D continuity, momentum and energy equations, k-εequations of trubulent model, 3-D flux equations of heat radiation, and so on. In order to treat moving boundaries of burning surfaces, the tracking technique with marked grid is proposed.The studied results indicate: 1) The distribution of 3-D flow parameters in the passages of finocyl grain of SPRM can be obtained by coupled solution for aforementioned equations. 2) Using the tracking technique with marked grid, automatic judgement and treatment can be realized by computer, and the problem of the complex 3-D burning boundaries moving may be solved better. 3) The geometry match between fin-canals and main passage, and intense degree of propellant mass addition will intensely influence the parameter distribution of flow field, even returning flow and eddy will occur. This 3-D flow field will lead to 3-D erosion combustion. However, no unchanged flow rule may be followed. Therefore, for concrete geometry disign and burning rate, the particular calculation must be carried out, and the particular flow field can then be obtained. 4) In certain condition, near down stream of 3-D fin-canals mass-addition flow, the obvious circumferential eddy flow can be caused. When the fin-canals are designed at tail of combustion chamber, the 3-D flow condition will produce 3-D influence for flow, combustion and ablation of the back and throat of submerged nozzle.