Experimental Investigation of Heat Transfer in Separated Flow on a Highly Loaded LP Turbine Cascade

摘要

Today aerodynamic design tools and CFD-codes provide excellent quality in predicting 2D and 3D flows in turbine components. Nevertheless correlation and numerical methods are not able to predict beat flux in a satisfactory accuracy for complex heat transfer problems for example 3D film cooling mixing zones or areas of separated flow. In order to close part of these gaps in knowledge and to improve the understanding of the interaction between the flow pattern and the beat transfer phenomena experimental investigations were carried out focused on 2D separated flow on the pressure side leading edge of the highly loaded low pressure turbine cascade named T106-300. The cascade was instrumented with pressure taps and glue-on hot-film sensors. The pressure taps provided the static profile pressure distribution. The hot-film anemometry technique normally is used to detect boundary layer development; moreover a procedure will be presented to evaluate the heat transfer coefficient as well. Supplementary boundary layer traverses with a 1D hot-wire probe were carried out at positions inside and downstream of the separation. The dimension of the separation tip to 60% chord was varied by the incidence angle. By variation of Reynolds number and Mach number a data set is available which will be put down to a correlation.