串联式底排火箭复合增程的推力损失研究

NUMERICAL STUDIES OF THRUST LOSS ON SERIAL BOTTOM EXHAUST-ROCKET COMPOUND EXTENDED RANGE PROJECTILES

利用分区技术 ,从二维轴对称Euler方程出发 ,应用有限体积TVD格式 ,数值模拟了火箭喷管出口截面处于底排装置空腔中不同位置时的燃气流场 ,并进行了推力损失研究 .结果表明 ,在底排装置空腔中的流动特性很复杂 ,存在涡系结构 ,底排出口截面上的密度、排气速度和压力是影响推力损失的主要因素 ,得出了推力损失随喷管出口截面在底排装置空腔中不同位置时的变化规律 。

Based on zonal approach, flow field of nozzle outlet in different position of the cavity of bottom exhaust has been numerically simulated and thrust loss has been studied. The 2-D axisymmetric Euler equations and implicit finite volume TVD schemes are applied. The results show the characteristic of flow inside cavity of bottom exhaust is very complex, and the structures of volute exist, it also presents three major factors of causing thrust loss that are the distribution of density, the exhaust velocity and pressure on the section of outlet. Finally the variational law of thrust loss by different position of nozzle outlet in the bottom exhaust cavity is carried out. The results can provide theoretical foundation for the structure design of serial bottom exhaust-rocket compound extended range projectiles.