Numerical Study on Effect of Lower Edge Plate Hole on Flow and Heat Transfer of Internal Cooling Passage in Trailing Edge of Turbine Blades

Abstract

The air outlet hole of lower edge plate of turbine blade can influence the flow and heat transfer performance. The numerical simulation method is used to study the effect of air outlet hole of lower edge plate on the flow and heat transfer performance in internal cooling passage of turbine blade from the trailing edge and the lower edge plate. The effects of hole size, hole shape and hole position of the lower edge plate on the flow coefficient and outflow rate of the overflow hole in the trailing edge, total pressure coefficient in trailing edge passage, and heat transfer property of inner-cooling cavity wall in the trailing edge are analyzed. The results show that the diameter of the hole has great influence on the flow coefficient distribution of the lower edge of the plate. With the increase of the hole diameter, the flow coefficient of the overflow hole of the trailing edge is decreased. With the increase of hole diameter, the tailing edge outflow ratio and pressure loss in the cold passage in the trailing edge are decreased, and the average heat transfer coefficient of the internal cooling passage is increased. The shape of the hole is of small effect on the flow and heat transfer in the upstream inner cold passage. The change of the hole position has small effect on the heat transfer coefficient of the inner wall of the inner cold passage, and has great effect on the local part.

Keywords

• turbine blade
• air outlet hole of lower edge plate
• internal cooling passage
• flow coefficient
• flow distribution
• heat transfer coefficient