关键词: 扰流柱;旋转;数值分析;流动特性;压力损失

Abstract: Using pin-fin structure in turbine blade trailing edge helps to improve cooling air allocation and the uniformity of flow filed in the trailing edge slots of turbine blades. However， the added pin-fins inevitably increases the resistance to the fluid flow. Therefore， the geometry matching of pin-fin and trailing edge slots have obvious influence on heat transfer of turbine blade. With M0 as a reference model of a real turbine trailing edge with no pin-fins， this paper adopted the numerical method to compare the flow fields in the trailing edge of three models with different pin fin structures under both static and three rotating speeds. M1 has a single row of 13 pin-fins with a diameter of D=2mm. M2 and M3 have two staggered rows of pin-fins with a respective number of 16 and 17 and a diameter D=1.2mm. Only a slight difference in pin fin arrangement exists near Slot 1 between the two models. The results demonstrated that： （1） The pin-fin located in trailing passage can increase the uniformity of flow field， have a big influence on flow characteristic of #1~3 trailing slots， M2 and M3 with two staggered rows of pin-fins has a better results than M1 with a single row. （2） Compared to M0， the added pin fins in M1， M2 and M3 models cause a moderate increase in pressure losses. The pressure loss coefficients of M2 and M3 are of the same level， and are slightly higher than that of M1 due to higher disturbances to the flow. （3） Increasing blade rotating speed causes continual decrease of pressure loss coefficient， but the flow structure in the slots of all the four models is not evidently changed.

Key words: Pin-fin;Rotation;Numerical investigation;Flow characteristics;Pressure loss