Numerical Study On Flow And Heat Transfer Characteristics Of Turbine Blade Laminate Cooling Structure

Turbine blade cooling technology plays an extremely important role in improving the performance of turbo-engines.As the performance of aero-engines increases,the gas temperature before the turbines also increases,which puts higher demands on the performance of turbine blade materials.In addition to developing new materials for turbine blades to increase their heat resistance limits,a more efficient and easier to implement solution is to enhance the cooling heat transfer of the blades.Among all the cooling methods,the layer plate cooling is a cooling film such as gas film cooling,impact cooling,convection cooling,and turbulence column strengthening,which has the advantages of greatly improving the gas temperature before the turbine and high cooling efficiency.In this paper,the aero-engine turbine blade laminate cooling structure is taken as the research object,and the flow and heat transfer in the laminar structure of the rotor blade trailing edge and rotor chord length are numerically simulated,and the calculation model is analyzed and studied.The model structure with better cooling effect is intended to lay a solid theoretical foundation for the design of the turbine blade cooling structure in the future.For the rotor model,the Reynolds number,the arrangement of the spoiler column,the influence of the impingement hole and the film hole on the coolin g efficiency and the flow field structure are mainly studied.The shape of the spoiler column is the most common cylinder.The results show that the cooling efficiency of the fork row spoiler column is higher than that of the side row spoiler column.In the same arrangement,increasing the impact hole and the film hole and the Reynolds number can effectively improve the cooling effect,but the impact hole and the film hole The increase will affect the structural strength of the blade,and the gradual increase of the Reynolds number will become less and less obvious.The overall flow field structure of the fork row and the smooth flow field is similar,and the difference is mainly near the first row of the spoiler column.For the arrangement of the fork row,the first row of the flow column is opposite to the impact hole,and the impact of the fluid on the wall surface on the first row of the spoiler column is strong.Based on the research of rotor model,the unit cooling model is used as the structure of double impingement pores.The numerical simulation of the shape and arrangement of the spoiler and the Reynolds number on the cooling model of the stator layer are found.The model has the best cooling effect,while the diamond has the worst cooling effect.Like the rotor model,the cooling efficiency of the fork row is higher than that of the row,and the increase of the Reynolds number has a marginal effect on the improvement of the cooling effect.The difference in the overall flow field structure between the fork row and the smooth flow field is mainly due to the fact that the shedding vortex structure behind the spoiler column of the impingement hole is more obvious.However,for a rhombic spoiler,whether it is a fork or a row,because the pressure gradient of the modified structure is small relative to the cylinder,when the fluid is facing the diamond,there is no obvious shedding vortex and recirculation zone behind it,and the length of the trail is also very short.