高速旋转光滑面迷宫密封内流动和传热特性的研究

Investigations on the Flow and Heat Transfer Characteristics in High Rotating Smooth Labyrinth Seals

采用三维计算模型,分析了在2种流量和不同转速时燃气轮机用收敛型和发散型高速旋转光滑面迷宫密封内的流动形态和传热特性.数值预测得到的光滑面迷宫密封的间隙热系数与试验数据吻合良好,验证了所采用数值计算方法的可靠性.结果表明:对于收敛型和发散型光滑面迷宫密封,在相同流量下,间隙热系数均随着旋转轴转速的提高而增加;在相同转速下,大流量时的间隙热系数小于小流量时的数值;在相同流量和转速时,2种型式光滑面迷宫密封的间隙热系数近似相等.

The flow form and heat transfer characteristics in convergent and divergent smooth labyrinth seals used for gas turbine at different rotating speeds with two kinds of leakage flow rate were analyzed by using the three dimensional computational model. The windage thermal factors of labyrinth seals with smooth stator obtained by numerical predictions were well agreed with the experimental data. The reliability of the numerical computation method adopted is validated. The results show that, for the convergent and divergent labyrinth seals with smooth stator, the windage thermal factors both increased with the rotating speed increasing at the same leakage flow rate. The windage thermal factor under high leakage flow rate is less than that under low leakage flow rate at the same rotating speed. The windage thermal factors of two type＇s labyrinth seals with smooth stator are approximately equal to each other at the same rotating speed and leakage flow rate.