Influence of Sweep on Tip Regions Flow Unstability in a Highly Loaded Fan Rotor
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摘要: 以超高负荷两级风扇第一级前掠转子为研究对象,通过定常和非定常数值模拟手段对近失速点叶尖流场进行了深入分析。为探索失稳机理,与同等气动性能下的后掠转子进行了对比。结果表明:前掠转子在近失速工况下泄漏涡涡心并未发生破碎,其流动失稳是由于端壁机匣处的低能流体集聚所致。而后掠转子的泄漏涡与激波干涉导致其向下游发展中发生破碎,表现出与常规转子相似的失速特征。Abstract: Steady and unsteady three-dimensional viscous flows are calculated to obtain flow fields under various operat-ing conditions for two-level highly loaded transonic forward-speep rotors and to advance the understanding of the flowfield near tip regions. The study shows that with the forward-swept rotor,the tip clearance vortex does not break downeven under the stalled condition. A low momentum area originating from the endwall boundary layer prevents incomingflow from passing through the pressure side of the passage and initiates stall inception. With the backsweep rotor,thecore tip clearance vortex breaks down just like when a conventional rotor does near the stalled condition.
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Key words:
- sweep /
- stability /
- leakage vortex /
- vortex breakdown
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[1] Sirakov B T，Tan C S.Effect of unsteady stator wake-rotor doub-le-leakage tip clearance flow interaction on time-average compres-sor performance[J]. Journal of Turbomachinery，2003, 125(25):464～473 [2] Adamczyk J J，Celestina M L，Greitzer E M.The role of tipclearance in high-speed fan stall[J]. Journal of Turbomachin-ery, 1993, 115(1):28～39 [3] Gerolymos G A，Vallet I.Tip-clearance and secondary flows in atransonic compressor rotor[J]. Journal of Turbomachinery，1999, 121:751～762 [4] Chima R V.Calculation of tip clearance effects in a transoniccompressor rotor[J]. Journal of Turbomachinery, 1998, 120:131～139 [5] Smart M K，Kalkhoran I M.Flow model for predicting normalshock wave induced vortex breakdown[J].AIAA Journal，1997, 35:1589～1596 [6] Wadia A R，et al.Inner workings of aerodynamic sweep[J].Journal of Turbomachinery, 1998, 120:671～682 [7] Passrucker H，Engber M.The effect of forward sweep in a tran-sonic compressor rotor[J].Proceedings of the Institution ofMechanical Engineers，Part A: Power and Energy，2003，217:357～365 [8] McNulty G S，et al.The impact of forward swept rotors on tip-limited low-speed axial compressors[J]. Journal of Turboma-chinery, 2004, 125:445～454 [9] 卢新根.轴流压气机内部流动失稳及其被动控制研究[D].西北工业大学, 2007 [10] Van Zante D E，Strazisar A J，Wood J R，Hathaway M D.Rec-ommendations for achieving accurate numerical simulation of tipclearance flows in transonic compressor rotors[J]. Journal ofTurbomachinery, 2000, 122:733～741 [11] Hoeger M，Fritsch G，Bauer D.Numerical simulation of theshock-tip leakage vortex interaction in a HPC front stage[J].Journal of Turbomachinery, 1999, 121:456～468 [12] Krause E.Axial flow in slender vortices[A]. Proceedings ofFifth World Congress on Computational Mechanics[C], 2002 [13] Vo H D，Tan C S, Greitzer E M.Criteria for spike initiated rota-ting stall[J]. Journal of Turbomachinery, 2008, 130 -
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