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Indexed by:期刊论文

Date of Publication:2018-02-01

Journal:PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING

Included Journals:SCIE、EI

Volume:232

Issue:2

Page Number:374-387

ISSN No.:0954-4100

Key Words:Dimpled surface; highly loaded compressor cascade; flow control; topological structure; numerical simulation

Abstract:This study investigates the influence of geometry parameters of dimples on the blade surface in a high-turning linear compressor cascade. Four arrays of dimples with a depth-to-diameter ratio of 0.25 and the depth varying from 0.1mm to 0.6mm in six different configurations were erected to explore their effects on loss coefficients, streamline patterns, topology structure as well as vortex structure. The dimple configurations were evenly distributed among 42-65% axial chord on the suction surface. The Reynolds-averaged Navier-Stokes method was used in the computational investigation under the nominal condition. The results show that the dimples with proper size can positively affect the flow loss and flow pattern. The larger dimples do not dramatically overtake the smaller ones in loss reduction, suggesting that there exists an optimal size of dimples in loss reduction within compressor cascades. The total number of singular points and separation lines in the cascade are both reduced under the dimple configurations. Furthermore, the vortex structures of the prototype and a prominent dimple configuration were depicted in detail. Passage vortex plays a dominant role in organizing the fluid within the cascade. The dimple configurations can suppress the migration of passage vortex along the spanwise direction and thereby decreases its influence region.