Detailed Flow Investigation in a Ribbed Turbine Blade Two-Pass Cooling System

Kurzfassung

The Particle Image Velocimetry (PIV) is applied to a multi-pass cooling system in order to obtain complete flow field maps within the flow passages. The cooling system consists of a trapezoidal leading edge channel, a 180 deg. bend and an almost rectangular second channel. The cross sections of the channels were adapted to the shape of a typical turbine blade. It has ribbed walls in both channels to enhance heat transfer performance. Ribs are placed at the top and bottom walls of the channels. The high quality of the obtained results encourages the application of two-component PIV to the rotating system. The system was analyzed at the German Aerospace Center (DLR) with a small scaled model and at the Institute of Aerospace Thermodynamics (ITLR) of the Stuttgart University with a large scaled model to ease near rib flow analysis. Results of heat exchange are not the objective of this paper; they are investigation topics of the ITLR which is in close cooperation [SCHUBERT (2003), ISABE].