通过CFD数值模拟, 探究了畸变网阻力系数与畸变网后马赫数的关系, 揭示了来流马赫数大于临界马赫数以后, 总压损失会急剧增加以及临界马赫数的大小受圆柱之间距离影响的物理机制。研究表明, 总压损失急剧增加是因为来流马赫数大于临界马赫数以后, 流场中出现正激波和斜激波, 造成很大的激波损失;圆柱稠度大时, 喉道处更早达到声速, 在扩张段中形成斜激波, 在较低进口马赫数时达到临界状态。
This paper investigates the relationship between drag coefficient and the Mach number after distortion net and reveals the mechanisms of the rapid increase in total pressure loss when the upstream mach number exceeds the critical mach number based on CFD simulation.The results show that the normal shock wave and oblique shock wave occur in the flow field and result in the rapid increase in total pressure loss when upstream Mach number is beyond the critical Mach number.The critical condition occurs at lower inlet Mach number when the solidity of cylinder increases because the throat reaches the acoustic speed and oblique shock wave emerges in the diffuser part.
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