热声回热器内声场数值模拟研究

Numerical study of sound field in thermoacoustic regenerator

对热声系统板叠及其附近流域进行了声场、流场特性的数值模拟研究。通过不同计算方法的对比,网格独立性验证等确定了误差最小的二维可压缩湍流模型。模拟结果分析了典型工况下热声回热器内部的压流分布特点,观察了板叠末端涡结构的周期性,并且对比了不同周期下涡结构的变化。结果表明,在压力场达到稳定后,由于流场的粘性,使得回热器内速度场的稳定具有滞后性,两者的稳定并不同步。

The stack of a standing-wave thermoacoustic refrigerator was studied. The acoustic pressure and hydro processes near and within a thermoacoustic couple were simulated. The influences of numeric methodology on the simulation of nonlinear thermoacoustic process were studied. The distribution of static pressure and volume velocity amplitude in the system were discussed. Meanwhile,the vortex structure at the end of the stack was observed and compared the vortex structure under different cycle. The results showed that,because of the viscous effects,the stability of the velocity field in the regenerator is lag compared with the pressure field.