This study focuses on multi-jet impingement for gas turbine geometries in which the objective is to understand the influence of the roughness elements on a target surface to the heat transfer. Current work has proven that implementing roughness elements for multi-jet impingement target surfaces has increased heat transfer ranging anywhere from 10-30%. This study has chosen to investigate three different roughness elements, elliptical in cross-section, to compare to smooth surface geometries for multi-jet impingement. An experimental was taken for this study to extend the current knowledge of multi-jet impingement geometries and to further understand the heat transfer performance. A temperature sensitive paint (TSP) technique was used to measure the heat transfer on the target surface, in which the local temperature was measured to estimate area averaged heat transfer coefficient (HTC) and row averaged HTC. In order stay consistent with literature, non-dimensional parameters were used for geometry locations and boundaries. For this study, the Reynolds number range, based on jet diameter and mass flux, is 10-15k. The X/D (streamwise direction), Y/D (spanwise direction), Z/D (channel height direction), L/D (thickness of the jet plate) constraints for this study are 5, 6, 3, and 1 respectively. From the local heat transfer distributions of the different roughness elements, it is concluded that the inclusion of these elements increases heat transfer by 2-12% as compared to a flat/smooth target plate. It is therefore recommended from this study, that elements, elliptical in shape, provide favorability in heat transfer for gas turbine configurations.
Bachelor of Science in Mechanical Engineering (B.S.M.E.)
College of Engineering and Computer Science
Mechanical and Aerospace Engineering
Orlando (Main) Campus
Length of Campus-only Access
Medina, Marc A., "An Experimental Investigation of Heat Transfer for Arrays of impingement Jets onto the Featured Surfaces with Cylindrical and Elliptical Raised Surfaces" (2016). Honors Undergraduate Theses. 131.