异形截面同心筒燃气流动特性数值研究

摘要

Flow characteristics and behaviors of the rocket exhaust plumes in the round⁃outside and square⁃inside section were simulated,in order to meet requirements of concentric canister launch( CCL) system for some special missiles with irregular section or folding rudders/wings.First,a three⁃dimensional numerical model of Navier⁃Stokes equation for compressible gas was established based on basic features of the exhaust gas discharging from the canister.Then some calculations and analyses,involving typical flow phenomena,interference effects and influence factors of the discharge gap,were performed for traditional CCL with a double⁃layer cylinder structure.Last,typical phenomena of the exhaust plume discharging from an irregular section CCL were researched.Results show that the discharge gap plays an important role on behaviors of the exhaust plume flow. Internal pressure of the CCL increases with the decrease of the discharge gap.The CCL with round⁃outside and square⁃inside section has a smaller equivalent area,due to changing the discharge condition of the exhaust gases,than a double⁃layer traditional CCL system.%为满足异形截面或带有折叠舵翼的导弹利用同心筒优点进行发射的需求，对外圆内方截面形式的类同心筒发射过程燃气流动特性进行计算和分析。从燃气流动基本特性出发，建立基于三维可压缩气体N⁃S方程的数值计算模型；进而针对传统双层圆筒结构，对同心筒发射的典型流动现象、作用效应和燃气排导间隙的影响等进行计算和分析；结合外圆内方截面的类同心筒结构，对异形截面同心筒发射的典型现象进行研究。计算结果表明，同心筒发射时的燃气排导间隙对流动有着重要影响，排导间隙的减小，会增强发射筒内压强；采用外圆内方异形截面，会进一步改变燃气排导状态，使燃气排导的等效面积小于相同排导面积的双层圆筒结构。