E143 旋回を伴うフイルム冷却のタービン翼端壁部冷却への適用について(OS-18: 熱・物質移動の計測および現象解析(4))

抄録

This paper describes an experimental study on film cooling effectiveness of a circular and a fan-shaped film cooling holes with a swirling film coolant injected through the endwall of a high-loaded 1st nozzle. The film cooling effectiveness on the endwall of the enlarged 1st nozzle of E^3 turbine was measured by using PSP techniques. It appeared from the experimental results that the film cooling effectiveness of a circular hole was improved by increasing the angle θ of two impingement jets inside the cavity, which is used both to cool internal wall and to produce a swirling motion of film coolant. On the other hand, it was found that there exists an optimal jet angle between θ=5 to 10 degrees in the case of a fan shaped film cooling hole. Thus the new film cooling method with swirling cooling air has been demonstrated to maintain its high from cooling effectiveness even under such a complicated flow field.