Numerical study on swirl cooling flow, heat transfer and stress characteristics based on fluid-structure coupling method under different swirl chamber heights and Reynolds numbers

•External mainstream region, blade solid region and swirl cooling region are established.•Interaction between blade solid and swirl cooling is analyzed by fluid-structure coupling method.•Swirl cooling flow and heat transfer characteristics, solid region thermal and aerodynamic load are researched.•Swirl chamber height and coolant chamber inlet reynolds number are changed. In this study, a three-dimensional swirl cooling model coupled with high temperature mainstream cascade channel and blade leading edge solid region is established to simulate the flow, heat transfer and stress characteristics. The fluid-structure coupling model is utilized to analyze the interaction of external mainstream, solid blades and swirl cooling air. Six different swirl chamber heights are selected to explore the optimal height which is the most beneficial to gas turbine blade operation. Finally, influences of coolant chamber inlet Reynolds number on swirl cooling performance are discussed in detail. Results show that the temperature distribution of blade solid region is highly related to swirl cooling effect. Compared with aerodynamic load, the thermal load behaves more significant effects for blade stress conditions. As the swirl chamber height increases, the swirl cooling heat transfer performance gradually decreases, and the flow resistance also gradually decreases. The comprehensive heat transfer factor is introduced to evaluate the swirl cooling overall performance. When swirl chamber height is 19 mm, it has higher heat transfer capacity and lower flow resistance, and the comprehensive heat transfer factor is the highest. The Reynolds number has a strong influence on heat transfer performance. In order to avoid high aerodynamic losses, the Reynolds number should be selected appropriately.