入口流量对变燃速发射药交界面位置影响数值计算

Numerical Simulation on Inlet Flow Rate for the Variable-burning Rate Propellant Interface Position

在间断式变燃速发射药成型工艺生产条件下,探索内外层入口流量变化及关系对发射药内外层交界面尺寸的影响,采用Bird-Carreau方程描述单基发射药的流变学特征,利用有限元方法模拟两种熔体在共挤出流道内的三维等温流动。研究表明:内外层交界面随着内芯皮料流量比值的变化呈线性关系,在50∶1时所得模拟结果与实际挤出药粒截面尺寸的最大相对误差为8.3%,在工程允许误差范围内,可以指导间断式双层变燃速发射药的实际生产。

In the discontinuous co- extension process,the relationship between entry flow rate with the interface layer position of variable burning rate propellant was explored. Bird- Carreau equation was used to describe the rheology of single base propellant feature. The finite element method was used to simulate two kinds of melt in the extrusion of 3-D isothermal flow. Result showed that radius of inner and outer layer interface has a linear relation with the change of inner and outer layer flow ratio,especially in 50∶1 flow rate of inner layer than out layer,the simulation results and the actual extrusion size grain section,the maximum relative error was 8. 3%. In the engineering allowable error range,it would be helpful to guide the intermittent double variable the actual production rate propellant combustion.