A Detailed Study of the Interaction Between Two Rows of Cooling Holes

Abstract

An optimal design of film cooling is a key factor in the effort of producing high-efficiency gas turbine. Understanding of the fluid dynamics interaction between cooling holes can help engineers to improve overall thermal effectiveness. Correct prediction through modeling is a very complex problem since multiple phenomena are involved such as mixing, turbulence, and heat transfer. The present work performs an investigation of different cooling configurations ranging from single hole up to two rows. The main objective is to evaluate the double-rows interaction and the effect on film cooling. Strong nonlinear effects are underlined by different simulations, while varying blowing ratio (BR) and geometrical configuration of cooling holes. Meanwhile an initial analysis is performed using flat plate geometry, verification and validation is then extended to realistic stage of high pressure (HP) turbine. Multiple cooling holes configurations are embedded on the pressure side (PS) and suction side (SS) of the single stage. The main outcome is the verification of the thermal effectiveness improvement obtained by cooling jets interaction of multiple rows design. The effects of curvature surface and frame of reference rotation are also evaluated, underlying the differences with standard flat plate test cases.