The Effect of Blade-Wakes on the Performance of Short Dump-Diffuser Type Combustor Inlets

Experimental results are presented of the effects of flow distortions, generated by a compressor cascade, on the performance of a short annular dump-diffuser type combustor inlet. The distance between the cascade and the diffuser entrance plane was varied. The losses increase substantially when this distance becomes small. In most of the tests the losses turned out to be minimum at a distance of about two blade-chord lengths. When the cascade was removed, the losses were higher than this minimum value. Evidence is presented that the radial blockage factor rather than the total blockage factor determines the magnitude of the losses.