Transonic Cascade

In order to investigate the continuous flow through turbomachinery blading the institute set up a transonic test cascade wind tunnel. Within this test cascade turbomachinery blades can be arranged linearly (Linear Cascade – LinCa) or circumferentially (Annular Cascade - Anca). Optical access to the flow section is enabled through windows in the test rig. Together with pressure and temperature transducers modern laser-optical equipment is used for flow analysis in subsonic and transonic flows. For the linear arrangement the blade cascade can be exchanged easily so that various blading can be investigated.


For the annular setups the facility was designed to be compatible to the Transonic Test Turbine Facility (TTTF). This allows back-to-back tests of the turbine duct setups in two different machines with different inlet flow complexity.

The following video shows the transonic test rig located in the first basement; you will see (from the left): two component LDV system including processors for real-time signal processing (Fourier Transformation) and a PC for data acquisition, data acquisition system for pressure and  temperature, and digital interferogram evaluation system. In the laboratory, you can see the transonic test rig with a Laser Doppler Velocimeter traverse (including the probe) in the front and the inlet piping from the right. The laboratory can also be used for hot turbine tests runs sucking air through acoustic insulators from the outside.

Transonic Cascade Lab


Institute of Thermal Turbomachinery and Machine Dynamics

Graz University of Technology
Inffeldgasse 25/A
A-8010 Graz

Tel: +43 (0)316 873 - 7226
Fax: +43 (0)316 873 - 107226