Session: 12-07 Optimization of Film Cooling Geometries

Paper Number: 82726

82726 - Evaluation of Adjoint Optimized Hole - Part II: Parameter Effects on Performance 

In a previous study from our laboratory, a computational adjoint based optimization method was used to design shaped film cooling holes fed by internal co-flow and cross-flow channels.  The associated RANS computations predicted that the holes optimized for use with cross-flow (X-flow_AOp) and co-flow (Co-flow_AOp) would increase adiabatic effectiveness by 150% and 200%, respectively, compared to a baseline 7-7-7 shaped hole. Experimental validations of these performance predictions are presented in companion paper (Gutierrez et al., 2022).  Although the experimental values were significantly lower than the computational predictions, the adiabatic effectiveness for the adjoint optimized holes was measured to be significantly higher than that for the baseline 7-7-7 shaped hole.  Specifically, the X-flow_AOp hole was 80% higher and the Co-flow_AOp hole was 60% higher.  In this study, the effects of various key parameters on the performance of the adjoint optimized holes were determined.  For these experiments the internal channel velocity ratios ranged from VR_c = 0.2 to 0.6, both co-flow and counter-flow conditions were used, and the density ratio ranged from DR = 1.2 to 1.8.  These provided a quantification of the performance of the adjoint optimized holes over a wide range of operating conditions encompassing engine relevant conditions. Adiabatic film effectiveness measurements and thermal field measurements are made to understand the performance variations and to compare with other hole geometries, such as 15-15-1 RI (rounded inlet) and 7-7-7 SI (sharp inlet). The experimental results were also compared to computational predictions.  

Presenting Author: Christopher Yoon UT Austin

Presenting Author Biography: Chris Yoon is a PhD student in mechanical engineering, working under Dr. David Bogard at the University of Texas at Austin. His research balances both experimental and computational study of gas turbine film cooling.

Authors:

Christopher Yoon UT Austin
Daniel Gutierrez UT Austin
Michael Furgeson UT Austin
David Bogard UT Austin
Todd Oliver UT Austin