加力燃油泵压出室非设计工况内流特征数值模拟
Numerical simulation on internal flow characteristics in the discharge chamber of an afterburning fuel pump under off-design conditions
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摘要: 针对某型航空发动机加力燃油泵隔舌空蚀破坏,采用滑移网格技术模拟泵内非定常流场,揭示了压出室在典型非设计工况下的内流特征,研究了隔舌处的空化机理.计算结果表明:大流量工况,扩散管锥形段存在大小两个分离涡,而环形腔室隔舌段燃油以相切方式流经隔舌壁面,无明显流动分离,不会发生空化;而小流量工况,扩散管锥形段内两分离涡扩展到大部分区域,右半侧部分阻滞燃油在反向流向涡作用下,绕流隔舌上部,在隔舌下游形成了明显分离涡,导致隔舌壁面静压急剧降低,进而引发空化,产生空蚀破坏.Abstract: The unsteady flow in an afterburning oil pump on a certain type of aero-engine was simulated for the uncommon cavitation damage problem near its casing tongue,with arbitrary sliding mesh technology.The discharge chamber internal flow characteristics at off-design conditions were investigated to find out possible conditions causing the casing tongue cavitation.The results showed that:under large flow-rate condition,there are two separated vortices of different sizes located in the cone-shaped tube passage,while the fuel flowed past the casing wall without obvious separation in the annular chamber,which hardly trigger cavitation;under small flow-rate condition,the two separated vortices extend to take up most part of the cone-shaped passage,incoming flow of the diffuser is choke up with a part of the fuel blocked at right side flowing back to the annular chamber around the tongue.As a result,serious flow separation is raised with a high pressure decrease,which is expected to generate cavitation and following damage on the casing tongue.
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Key words:
- afterburning fuel pump /
- tangent pump /
- discharge chamber /
- cavitation /
- separation
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[1] 陈乃祥,吴玉林.离心泵[M].北京:机械工业出版社,2003. [2] Bachert R,Stoffel B,Dular M.Unsteady cavitation at the tongue of the volute of a centrifugal pump[J].Journal of Fluids Engineering,2010,132(6):061301(6 pages). [3] Washio S,Fujiyoshi S,Takahashi S.Observation of cavitation inception in separating water flows through constricted channels[J].Proceedings of the Institution of Mechanical Engineers Part C:Journal of Mechanical Engineering Science,2009,223(9):2071-2080. [4] Washio S,Takahashi S,Uemura K,et al.Singular properties of flow separation as a real cause of cavitation inception[J].Proceedings of the Institution of Mechanical Engineers Part C:Journal of Mechanical Engineering Science,2008,222(4):667-678. [5] O’Hern T J.An experimental investigation of turbulent shear flow cavitation[J].Journal of Fluid Mechanics,1990,215:365-391. [6] 范宗霖,王革田.切线泵的试验研究[J].水泵技术,2002,(1):3-8. [7] 吴玉珍.部分流式切线泵在高效率条件下扬程系数的确定[J].化工设备与管道,2000,37(3):37-39. WU Yuzhen.Determination of head coefficient for part flow tangent pumps with high efficiency[J].Process Equipment & Piping,2000,37(3):37-39.(in Chinese) [8] Barske U M.Development of some unconventional centrifugal pumps[J].Proceedings of the Institution of Mechanical Engineers,1960,174(1):437-461. [9] 张剑慈,崔宝玲,李昳,等.低比转速开式叶轮高速离心泵的优化设计系统[J].机械工程学报,2006,42(7):19-23. ZHANG Jianci,CUI Baoling,LI Yi,et al.Optimum design system of low-specific open-impeller high-speed centrifugal pump[J].Chinese Journal of Mechanical Engineering,2006,42(0):19-23.(in Chinese) [10] 陈党民,李新宏,黄淑娟.部分流泵整机非定常流动数值模拟[J].工程热物理学报.2005,26(增刊):89-92. CHEN Dangmin,LI Xinhong,HUANG Shujuan.Numerical analysis of the unsteady flow field for a partial emission pump[J].Journal of Engineering Thermophysics,2005,26(Supplement):89-92.(in Chinese) [11] Barth T J,Jespersen D C.The design and application of upwind schemes on unstructured meshes.AIAA-1989-366,1989. [12] Hunt J C R,Wray A A,Moin P.Eddies,streams,and convergence zones in turbulent flows.CTR-S88,1988. -
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