Numerical simulation of flow and heat transfer in internal cooling blade channel with leading-edge

Flow and heat transfer in approximate real model of blade channel with leading-edge was analyzed by numerical simulation at static condition. The results show: three-dimensional vortices introduced by inclined ribs lead to a great impact on heat transfer in the cavity. Within one rib height range, vortices after ribs occur in both Y-Z and X-Y cross-sections, which makes heat transfer coefficients here in decrease. In X-Z cross-section, the second channel produces a pair of vortices in the opposite direction while the third channel results in just one vortex. Vortices in these two channels occupy the whole cross-section and increase flow resistance. The impingement and film flow play a leading role in heat transfer in leading-edge channel where vortex pair induced by impingement enhances flow mixing and stimulates heat transfer on suction and pressure sides, while high-speed film flow promotes this process. In the same flow conditions, average and local heat transfer on ribbed surface of the second channel perform the best, but the smooth first channel owns the highest comprehensive heat transfer performance due to its minimum total pressure drop in all the channels. With the increasing Reynolds number, local and average heat transfer on suction and pressure sides in each channel are enhanced in contrast with little change in the pressure drop coefficient.