摘要:
本文针对旋转射流风机不同动静叶片间距，采用非定常结合大涡模拟的方法研究了后导叶射流风机的内流特性、外流特性及声传播问题，主要结论如下：叶轮动静间距的可调余地较大；动叶中的卡门涡和叶顶泄漏涡，以及叶片前缘产生的近壁叶道涡组成了动叶组的特色涡，涡声的源头位于前缘和尾缘；流场外侧的湍流粘性和有效粘性加剧了湍流的声音耗散；压力的时间、频率特性与声压的时频特性呈正相关的关系，声压的幅射主要位于轴线四周。
The internal flow and outflow field characteristics, and sound propagation problems of the rotating jet fan with the behind guide vanes are studied using the combination of the unsteady flow and large eddy simulation. The main conclusions are as follows: the pitch between the impeller and the guide vanes has a bigger adjustable space; the rotor blades is the main sound source surface, the Karman vortex and tip leakage vortex, and channel vortex near the wall from the leading edge is characteristics vortex of the moving blades, the sound sources of vortex generators is located in the leading and trailing edge; the turbulent viscosity and effective viscosity of outflow field intensifies the dissipation of the turbulent sound; the pressure characteristics of time and frequency shows a positive correlation to that of the sound pressure, the radiation of sound pressure mainly point to the axis around.