叶顶间隙对离心叶轮气动性能影响研究Study on Influence of Tip Clearance on Aerodynamic Performance of Centrifugal Impeller
张楚华;王宝潼;栾辉宝;刘帆;
ZHANG Chu-hua,WANG Bao-tong,LUAN Hui-bao,LIU Fan(Xi'an Jiaotong University,Xi'an 710049,China)
摘要(Abstract):
使用非结构化网格上的有限体积法,数值研究一半开式离心压缩机叶轮的内部流场、气动性能随叶顶间隙的变化规律。对原始叶轮相对间隙a=1.8%,数值计算所得到的气动性能参数与实验值符合非常好;对大范围叶顶相对间隙a=0.9%7.0%内6种不同叶顶间隙下该叶轮的气动性能进行数值预测,随着叶顶间隙增大,离心叶轮气动效率、压比及转矩均降低,但变化曲线与线性函数相距甚远,呈现出典型的双平台变化关系。对所研究模型,综合考虑气动及强度振动因素,叶顶相对间隙最佳值取为2.6%,计算结果对离心压缩机设计具有一定的工程指导意义。
A finite volume method on unstructured grid is applied to numerically study the influence of tip clearance on the internal flow fields and aerodynamic performance of an unshouded centrifugal compressor impeller.For the basic impeller of relative tip clearance a = 1.8%,the calculated aerodynamic performance fits quite well the measurements.Then,the numerical prediction is carried out for the flow fields and aerodynamic performance for the impeller at six cases of relative tip clearance ranging widely within 0.9%~7.0%.The numerical results show that the aerodynamic efficiency,pressure ratio and toque all decrease as the tip clearance increases.However,the relationship between the aerodynamic performance and the tip clearance deviates far away from the linear function and appears dual plateaus sandwiched by two steep curves.For the impeller,the optimal relative tip clearance 2.6% is a compromise between aerodynamic and structural requirements.The results of this paper are of certain values in centrifugal compressor design.
关键词(KeyWords):
离心叶轮;叶顶间隙;气动性能
centrifugal impeller;tip clearance;aerodynamic performance
基金项目(Foundation): 国家自然科学基金项目(10572113)
作者(Authors):
张楚华;王宝潼;栾辉宝;刘帆;
ZHANG Chu-hua,WANG Bao-tong,LUAN Hui-bao,LIU Fan(Xi'an Jiaotong University,Xi'an 710049,China)
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