Enhanced performance of fast-response 3-hole wedge probes for transonic flows in axial turbomachinery

Abstract

This contribution presents the development, calibration, and application of a directional, three-sensor fast-response wedge probe for aerodynamic measurements in turbomachines. The probe is equipped with flush-mounted commercial fast-response miniaturized pressure transducers. Angular calibrations cover a wide range of Mach numbers (0.3-0.7). The angular range of the probe and linearity of the calibration maps is enhanced with a novel zonal calibration technique.. The effect of the pressure readings uncertainty on the retrieved flow variables is analyzed for different Mach numbers, and the effect of self-induced perturbations is discussed. The effects of the Reynolds and Mach numbers are studied through spectral analysis of the calibration tests together with CFD simulations. The data reduction methodology is explained and demonstrated with measurements performed in a single-stage high pressure turbine mounted in the compression tube facility of the von Karman Institute. The turbine was operated at subsonic and transonic pressure ratios (2.4 and 5.1) for a Reynolds number of 10 6 , representative of modern engine conditions. Time-resolved angular measurements were obtained at high speed conditions downstream of the rotor and allowed studying secondary flows and the rotor trailing edge shocks for different test conditions.

Design and Demodulation of a Fiber-Optic Fabry-Perot Sensor Applied in a High- Frequency Pneumatic System

“…As a conventional, accurate, and economical flow field measurement tool, pneumatic probes are widely employed in flow field studies. There are three commonly used types of pneumatic probes [14]- [16]: three-hole, five-hole, and sevenhole probes. With the development of gas turbines, aeroengines, and other high-speed flow devices, the demand for dynamic flow field measurements is increasing.…”