Compressor Stator Leading Edge Instrumentation

Abstract Leading edge instrumentation is commonly used for performance measurement in high-speed multi-stage compressor or whole engine testing. Due to spatial constraints and calibration requirements, it is infeasible to use the more accurate methods of a roving multi-hole probe or multi-headed rakes. In this work the parasitic losses and measurement accuracy of both Kiel shrouded, and bare Pitot probes is studied on the leading edge of a compressor stator. The trade-off between these two quantities with four different relative sizes of probe is measured in a single stage experimental compressor rig and supported with numerical calculations. Several comparisons are made to help guide an instrumentation designer to select the best instrumentation for their machines: whether the leadouts can be routed on the pressure side of the blade or should be internal to the geometry; the design of the intake of the Kiel shroud itself; and whether or not a Kiel shroud is even needed in a compressor application. In each case, the effect on the local operating point of the stage is examined as well as the detailed flow physics on the instrumented blade itself.