15th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
Authors
Abstract
This paper describes the setup, planned measurements and commissioning results of an experimental investigation on asymmetric inflow conditions in a transonic compressor. The inhomogeneities are caused by a variation of the inlet guide vane (VIGV) stagger angle in circumferential direction. The test vehicle is the Transonic Compressor Darmstadt 2 (TCD2) at Technical University of Darmstadt. This rig features extensive steady and unsteady traversable instrumentation in multiple measurement planes. Its 1.5-stage design is representative of a modern gas turbine compressor front stage. For gas turbines, power adjustment is accomplished by changing the stagger angle of all VIGVs simultaneously. The mechanism used, consisting of a unison ring and levers, is susceptible to mechanical failure that can lead to arbitrary asymmetries of the VIGVs. The test rig was therefore modified to enable individual stagger angles for all vanes during operation. This allows for a fine granular quantification of the effects of different asymmetric VIGV patterns or single vane mis-stagger on compressor performance, forced response, stall margin and behavior beyond the stability limit without the risk of systematic measurement errors due to re-assemblies of the rig. Research objectives, measurement procedures and techniques as well as initial results are presented within the framework of this paper.
ETC2023-377