计及几何参数变化的离心压气机特性分析

本文采用CFD软件对微型燃机的离心叶轮进行数值模拟,讨论了叶片数及分流叶片位置对叶轮性能的影响,并进行了流场分析。在本文研究的情况中,叶片数增加使得性能曲线左移,单个叶片载荷减小,损失增加,叶轮效率下降, 但是增压效果得到改善。分流叶片位置靠近主叶片压力面时,性能曲线右移,流通能力提高,同时会使分流叶片的载荷增大,当分流叶片靠近主叶片压力面时,则情况相反。

CHARACTERISTIC ANALYSIS OF A CENTRIFUGAL COMPRESSOR WITH DIFFERENT GEOMETRY PARAMETERS

To study the effect of the number of the blade and the circumferential position of the splitter on the centrifugal compressor, a numerical simulation on the centrifugal impeller of a micro gas turbine is made with the CFD software. Moreover, the analysis of the flow field in the impeller is done. The result shows that the performance curve moves to the right with the increasing of the number of the blade; the pressure on single blade increases; the loss of the flow increases; the positions of the flow loss center in both channels move towards the splitter, and the efficiency of the impeller reduces, but the pressure ratio of the impeller can benefit a little. As for the circumferential position of the splitter, three positions are studied, including the middle position, one close to the pressure side of the blade and one close to the suction side. The position of the splitter has greater effect on the performance if there are fewer blades. When the splitter is close to the pressure side of the blade, the performance curve moves to the right; the flux of the impeller increases; the pressure load of the splitter increases. When the splitter is close to the suction side of the blade, the situation is opposite.