Abstract:

The present study concentrates on the computational investigation of a new cooling configuration of a doublelayer cavity in the middle section of modern turbine blade. A three-dimensional NavierStokes code with standard k-ε turbulence model as well as wall functions is used to compute the flow and heat transfer characteristics for a combined impingement and film cooling configuration. The blowing ratio ranges of 0.6~2.0, and the Reynolds number based on the inlet velocity of the cooling air varies from 2 000 to 5 000. Details of the effect of the ratio of film hole diameter to jet hole diameter, D/d on hybrid cooling effectiveness are discussed. Numerical results show that a larger hybrid cooling effectiveness and a lower flow resistance are reached with the increase of the diameter of film cooling hole, while the diameter of impingement hole is fixed.

Key words: film,  , impingement,  , hybrid,  , cooling,  , heat , transfer,  , flow , resistance