GAS TURBINE VANE WITH ENHANCED COOLING

摘要

A gas turbine stationary vane having an airfoil portion and inner (36) and outer (38) shrouds. Five serpentine radially extending cooling air passages (51-55) are formed in the vane airfoil. The first passage (51) is disposed adjacent the leading edge (40) of the airfoil and the second passage is disposed adjacent the trailing edge. A first portion (80) of the cooling air enters the first passage (51), from which it flows sequentially to the second, third, fourth and fifth passages. Additional cooling air (83) enters the third passage directly, thereby bypassing the first and second passages and preventing over heating of the cooling air by the time it reaches the fifth passage. A radial tube (45) extends through the second passage and directs cooling air through the airfoil, with essentially no rise in temperature, to an interstage cavity (70) for disc (42, 43) cooling. Fins project (60-64) into each of the passages and serve to increase the effectiveness and flow rate of the cooling air. The fins in the first and fifth passages are angled so as to direct the cooling air toward the leading (40) and trailing (41) edges, respectively. In addition, the fins in the second through fifth passages are angled to retard flow separation as the cooling air turns 180 DEG from one passage to the next.