斜切反喷管粘性流场数值模

NUMERICAL SIMULATION OF VISCOUS FLOWFIELD IN A SCRAFED REVERSAL NOZZLE

关键词:  推力反向  特型喷管  计算流体动力学  数值模拟

Key words:  Thrust reversal  Unconventional nozzle  Computational fluid dynamics  Numericalsimulation

摘要:

为了在级间分离期间提供反推力，许多固体火箭发动机前端都装有一组斜切反喷管，由于反喷管气动型面具有尖点，并在超音速区有台阶，喷管内存在一系列激波，并伴有流动分离现象。从雷诺平均的非定常Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程出发，利用时间相关法，采用ＭａｃＣｏｒｍａｃｋ两步显格式，结合Ｂａｌｄｗｉｎ－Ｌｏｍａｘ代数湍流模型，数值模拟了斜切反喷管流场。计算得到的壁面压强分布与风洞吹风实验测得的压强分市相当一致。

Abstract:

any solid propellant motors use a set of scrafed reversal nozzles located on the forward of the motors to provide reversal thrust during staging. Because the gasdynamic contour of reversal nozzle is not smooth and has a step in supersonic flow region, a series of shocks and flows separation in boundary-layer exists in flowfield of reversal nozzle. The viscous flowfields in scrafed reversalnozzle are simulated based on Renolds--average unsteady Navier--Stokes equations, with time-dependent method, MacCormack explicit scheme and Baldwin-Lomax algebraical turbulent model. Thepressure distributions obtained from computation are in good agreement with experimental data.