Experimental investigation of heat transfer of multi-row impingement jets in two-pass rectangular channel

Abstract

As temperature increases in gas turbines, efficiency and power increase. However, when gas turbines are exposed to high temperatures (2000 degrees C), the negative effect of mechanical and thermal forces on the equipment can be observed and can cause serious deformations. So-called deformations can occur very rapidly on primer blades and cause decreasing life of blades. Usage of alloys for extending the life of heat-affected blades and improving the effect of heat convection of the inside channel and top of blades are studied and admitted in the literature previously. In this study, different models with different jet Reynold numbers, jet geometry, jet size, jet layout, jet angle, and jet placement are studied. During this experimental study, effects of jet geometry, jet-target spacing, jet diameter, and Reynolds number coefficient are studied by using thermochromic liquid crystal method with different Reynolds number, round, square, and triangle type jets with the same hydraulic diameter on geometrically same model of blade cooling channel. At the end of the study, it is observed that usage of low Reynolds number with low diameter round jets and high Reynolds number with triangle jet plates are better to obtain a good convection heat transfer.