Experimental results are presented for film cooling effectiveness with injection from both a single row and multiple rows of holes with spanwise hole-to-hole spacings of three hole diameters. In the multi-row cases, the injection holes were arranged in staggered patterns with streamwise row-to-row spacings of five or ten hole diameters. Adiabatic wall temperature distributions near and downstream of injection holes were well visualized using a scanning infrared camera. The effect of mainstream pressure gradient was partially included. The additive nature of multi-row film cooling was demonstrated experimentally, in agreement with the Sellers superposition model.

This paper presents the experimental work on the leading edge cooling performance of an integrated impingement and pin-fin cooling configuration. Experiments are conducted for seven different spatial geometries under the simulated condition of 1400 degree Celsius-class actual turbine vane leading edge with the temperature ratio of 2.1. The Reynolds number of the hot gas side was 91000 and the cooling air Reynolds number was varied in the range of 5900–47000. The test piece surface temperature distributions were measured using an infrared camera with the correction by a thermocouple embedded on the test piece surface. The cooling effectiveness obtained from the experiments showed the superior cooling performance by the pin-fin integration. The effect of the cooling effectiveness enhancement was more than the cooling surface area increment. The detailed analyses of the cooling performance and the pressure loss characteristics are discussed.

No abstract

A series of experiments was performed to measure the cooling effectiveness of pin-fin type blades applicable to the first-stage blades of the high pressure turbine for the Advanced Gas Turbine of Japan (AGTJ-100A). Actual pin-fin type blades were used in three-dimensional hot cascade tests. Resulting cooling effectiveness distributions in chordwise direction showed relatively small deviation from the high average value and closely corresponded with analytical predictions. Another major finding was that for film cooling blades, particularly with a shower head film cooling, it is essential in the cascade tests to set the ratio between the coolant and mainstream temperature at values the same as real conditions. This makes it possible to simulate cooling air flow distributions in the blades of high temperature actual turbines using low temperature tests. This is also applicable to vanes with a shower head film cooling.

No abstract