Cooling effectiveness of effusion walls with deflection hole angles measured by infrared imaging

Experimental investigations were performed on the overall cooling effectiveness of three effusion cooling test plates. The test plates had different hole-spacing (PS/d² = 32.5 and 72), different deflection angle (β = 45° and 90°), and the same inclination angle (α = 30°). Although effusion cooling has been applied to advanced gas turbine combustors, its fundamental study seen in the open literature is limited. Using the infrared (IR) imaging technique, the current study documented distribution of the overall cooling effectiveness on the surfaces of above specified flat walls. Based on the IR measured cooling effectiveness data, different effusion cooling configurations (different PS/d² and β) were evaluated and the optimum configuration was determined. The current work demonstrated that the infrared imaging technique served as an ideal method to detail cooling characteristics in the combustor heat transfer research.