Abstract
This paper explores the effect of a prescribed intense shear flow
on the flow structures in an axial flow compressor cascade. An
approximate shear flow is generated in the test section of an open
circuit cascade wind tunnel by using a planar grid of parallel rods
with varying solidity. To study only the effect of shear, a
compressor cascade based on NACA65 series with a relatively low
camber was chosen. The cascade was analysed experimentally as
well as computationally (using ANSYS Fluent). The computational
results of the cascade were compared with the available measured
data. The results agreed well with the experimental data. Detailed
analysis of the numerical results was then carried out to explore the
complex flow features caused by the shear flow in a cascade. With
uniform flow, the secondary flow was found to be negligible from
experiments as well as from the computations. Therefore, in an
attempt to amplify secondary flow, a shear flow generator was
placed upstream of the cascade. Experiments showed quite
contrasting results with shear flow, as compared to the uniform flow,
in terms of the wake loss. Numerical analysis revealed the
formation of vortices in the wake of the cascade due to secondary
flows caused by the incoming shear flow and other interesting flow
features.
