Experimental investigation of reversed flow in a compressor cascade

An experimental investigation of reversed flow performance characteristics in a compressor cascade was conducted. The purpose was to gain a fundamental understanding of reversed flow in a compressor blade cascade, and to determine the effects of stagger angle and angle of attack on the reversed flow behavior in the cascade.

Tests were conducted at two blade configurations, one to simulate reversed flow in a compressor rotor and one to simulate reversed flow in a compressor inlet guide vane. Three stagger angles were tested for each configuration with an absolute angle of attack range from 70 to 130 degrees. The investigation included total and static pressure measurements upstream and downstream of the cascade as well as blade surface measurements.

Aerodynamic performance parameters were presented for a reversed flow cascade. Comparison of corrected total pressure loss curves suggested that blade rows of a compressor subjected to reversed flow may be treated as nearly equal loss producers. A comparison was made between total pressure loss coefficients from this investigation and experimental compressor performance. The total pressure loss coefficients compared favorably in magnitude and curve shape.