Vortex Shedding Mechanisms in Relation to Tip Clearance Flows and Losses in Axial Fans
نویسنده
چکیده
SUMMARY This paper outlines the importance of tip leakage flows in axial fans as a source of loss and relates the dimensionless loss analytically to a range of dimensionless parameters by application of a jet loss theory due to Rains. Improved vortex shedding models are also presented. From these models theoretical predictions of lift coefficient reduction are compared with published experimental data for isolated rectangular plates, with experimental tests for a single aerofoil adjacent to a wall with an oncoming boundary layer and correlations due to Lakshminarayana.
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