Design of Chalmers new low-pressure compressor test facility for low-speed testing of cryo-engine applications

Authors

Isak John Håkan Jonsson - Chalmers University of Technology, Gothenburg
G. Debarshee - Chalmers University of Technology, Gothenburg
C. Xisto - Chalmers University of Technology, Gothenburg
T. Grönstedt - Chalmers University of Technology, Gothenburg

Abstract

As a part of the ongoing Horizon 2020, ENABLEH2 project which aims to evaluate novel cryogenic fuel solution for commercial aviation, a new low-speed compressor test facility is being constructed. The work in Chalmers Laboratory of Fluids and Thermal Sciences focuses around the design and construction of this facility which will be utilized to study and verify the potential benefits of incorporating a heat management system in the intermediate compressor duct (ICD).   The test facility is designed to operate continuously at rotor midspan chord Reynold number up to 600,000 to allow for detailed aerothermal studies at a technical readiness level four. The two-stage axial compressor with the outlet guide vanes (OGV) and ICD is representative of the low-pressure compressor and ICD for a mid-size commercial jet engine. A 147kW electric motor at 1920 RPM provides power input to the compressor rotors which drives the circulation of the closed cycle facility. The mass-flow and pressure ratio are controlled by restricting valves upstream the compressor stages. A compact volute settling chamber with an integrated thermal control system is used to cool and remove non-uniformities in the flow exiting the restrictor before entering the compressor stages. Just upstream the rotor, a mesh is mounted to increase the turbulence levels to 3-4% at the leading edge of the variable inlet guide vane (IGV).   The compressor is mounted vertically to allow ease of access of the downstream ICD and mitigate non-axisymmetric mechanical loads. The compressor unit allows for optical and traverse access at two 18-degree sectors for all the rotor-stator interfaces. Upstream the OGV, there are four independent 360-degree access traverse systems. For measurement downstream the OGV in the ICD, a single ABB robot with a U-shaped probe mount provide full volume probing access. At the first design iteration the ICD is designed to be instrumented with multi-hole probes, hotwire anemometry and heat transfer measurement using IR-thermography.   The paper describes the facility and the process of achieving a high case similarity (engine representative) while maximising the quality of the experimental data over a large test domain, targets that often produce conflicting design demands.