圆盘结构下旋转爆震波的二维数值研究

Two-Dimensional Numerical Simulation of Rotating Detonation Wave in Plane-Radial Structure

关键词:  旋转爆震波  数值模拟  二维环形流场  爆震波参数

Key words:  Rotating detonation wave  Numerical simulation  Two-dimensional annular flow field  Detonation wave parameter

摘要:

为揭示圆盘形燃烧室内旋转爆震波的传播特性，以2H2+O₂+3.76N2为反应混合物，开展该结构下的二维数值研究。实现了旋转爆震波的成功起爆并得到了两种稳定的流场结构；详细分析了两种流场的特点，以及不同直径处爆震波参数及出口马赫数的变化规律。结果表明，旋转爆震波在壁面形成的反射激波对流场中的温度、压力分布以及流线都产生影响；随着直径的不断减小，旋转爆震波压力、温度以及传播速度都不断减小；流场稳定后，出口马赫数随时间的变化趋势与压力趋势相符，呈现“双波峰”特征。喷注总压为0.4MPa时，喷注入口的阻塞比为21%，超声速流动占整个出口流动的52.17%，出口流动的平均马赫数为0.98；当喷注总压降为0.2MPa时，入口阻塞比为20%，超声速流动占21.99%，出口流动的平均马赫数为0.95。

Abstract:

In order to reveal the propagation characteristic of the rotating detonation wave in plane-radial combustor，the two-dimensional numerical simulation was modeled in this structure for mixtures of 2H2+O₂+3.76N2. A steady rotating detonation wave was initiated in this annular flow field，and two kinds of steady flow field structure were obtained and analyzed in detail. The variation of detonation parameters at different diameter and Mach number in exit were also discussed. The distribution of temperature and pressure in flow field and the streamline are affected by the reflected shock wave formed at the inlet by the rotating detonation wave. The pressure，temperature and the propagation velocity decrease as the diameter decreases. When the flow filed is steady，the change of the pressure and the exit Mach number with time is similiar，having the "double peak" feature. When the filling pressure is 0.4MPa，the blockage ratio at injection inlet is 21%，and the supersonic flow accounts for 52.17% of the total outlet flow，and the average Mach number at the outlet flow is 0.98; when the filling pressure is 0.2MPa，they are 20%，21.99%，and 0.95，respectively.