Experimental Investigation of Unsteady Forces on Rotor and Stator Blades of an Axial Compressor

R. Mailach, L. Müller, K. Vogeler

abstract:

This paper presents experimental investigations of the unsteady blade forces in a four-stage low-speed research compressor. The unsteady pressures on the rotor and the stator blades of the first stage were determined using time-resolving piezoelectric pressure sensors. These sensors were equally distributed along midspan as well on the pressure and the suction side of a rotor and a stator blade.
The pressure distributions are analysed for different operating points between design point and stability limit as well as for rotating stall conditions. For stable operating points a strong influence of the passing wakes and of the potential effect of the blade row downstream can be observed.
A method to calculate the unsteady blade forces on the basis of the experimental data is presented. The results on the unsteady rotor and stator blade forces are discussed for the different operating conditions.

reference:

5th European Conference on Turbomachinery - Fluid Dynamics and Thermodynamics, Prague, Czech Republic, March 18 - 21, 2003.