Continuous adjoint aerodynamic optimization Design for multi-stage gas turbine with cooling air

Purpose: This paper aims to conduct the optimization of the multi-stage gas turbine with the effect of the cooling air injection based on the adjoint method. Design/methodology/approach: Continuous adjoint method is combined with the S2 surface code. Findings: The optimization of the stagger angles, stacking lines and the passage can improve the attack angles and restrain the development of the boundary, reducing the secondary flow loss caused by the cooling air injection. Practical implications: The aerodynamic performance of the gas turbine can be improved via the optimization of blade and passage based on the adjoint method. Originality/value: The results of the first study on the adjoint method applied to the S2 surface through flow calculation including the cooling air effect are presented.