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论文类型：期刊论文

发表时间：2019-02-01

发表刊物：AEROSPACE SCIENCE AND TECHNOLOGY

收录刊物：SCIE、Scopus

卷号：85

页面范围：48-60

ISSN号：1270-9638

关键字：Highly loaded compressor cascade; Dimple; Flow loss; Variation of inlet Mach number

摘要：In this paper, flow characteristics of dimpled compressor cascades are numerically discerned by solving the compressible Reynolds-averaged Navier-Stokes equations on structured grids over the inlet Mach number ranging from 0.3 to 0.8. Four rows of parallel, spherical dimples with a depth of 0.2 mm and a depth-to-diameter ratio of 0.25 are embedded along 10%-32% and 38%-60% chord of suction surface respectively. Results showed that two dimple configurations can both reduce the total pressure loss in all researched Mach number except that of 0.8. The suppression of three-dimensional separation near the hub-corner region is the primary cause of loss reduction. What's more, the separation bubble on the suction surface can be also eliminated or depressed due to the disturbance and higher level of turbulence kinetic energy within boundary layer. According to the distribution of axial vorticity in flow passage, the dimpled vortex can also suppress the migration of secondary flow along spanwise direction under a relative higher cross pressure gradient. (C) 2018 Elsevier Masson SAS. All rights reserved.