Feng Ye, Gao Yuping, Tang Ke, Jin Tao
Department of Energy Engineering, Zhejiang University, 38 Zheda Road, Hangzhou 310027, People's Republic of China.
Department of Mechanical Science and Engineering, University of Illinois, 1206 West Green Street, Urbana, Illinois 61801, USA.
J Acoust Soc Am. 2019 Mar;145(3):1417. doi: 10.1121/1.5094346.
A jet pump with an asymmetrical channel can induce a time-averaged pressure drop in oscillatory flow, which can effectively suppress Gedeon streaming in looped thermoacoustic engines. In this work, the flow characteristics and time-averaged pressure drop caused by a jet pump in turbulent oscillatory flow are investigated through numerical simulation. Through the analysis of the dimensionless governing equations, the emphasis is put on the effects of Womersley number and maximum acoustic Reynolds number on the performance of the jet pump. Meanwhile, the steady flow resistance coefficients are also measured numerically. The results indicate that the oscillatory flow resistance coefficients are relatively insensitive to Womersley number when it is less than 46. Moreover, the oscillatory flow resistance coefficients agree well with the steady state flow results, which validate the quasi-static assumption in turbulent oscillatory flow. However, further increasing Womersley number will lead to a reduction in the time-averaged pressure drop. The simulation method and results, as well as the hydrodynamic mechanism beneath the results, are presented and discussed in detail.
具有不对称通道的喷射泵能在振荡流中引起时间平均压降，这可有效抑制环形热声发动机中的热致流动。在这项工作中，通过数值模拟研究了喷射泵在湍流振荡流中引起的流动特性和时间平均压降。通过对无量纲控制方程的分析，重点研究了沃默斯利数和最大声雷诺数对喷射泵性能的影响。同时，还通过数值测量了稳态流动阻力系数。结果表明，当沃默斯利数小于46时，振荡流阻力系数对其相对不敏感。此外，振荡流阻力系数与稳态流动结果吻合良好，这验证了湍流振荡流中的准静态假设。然而，进一步增加沃默斯利数将导致时间平均压降减小。详细介绍并讨论了模拟方法和结果以及结果背后的流体动力学机制。
