Date of Award
Master of Science in Aerospace and Systems Engineering (MSASE)
Mechanical and Aerospace Engineering
Phillip M. Ligrani
George J. Nelson
Heat--Transmission., Nusselt number.
The present investigation involves testing the addition of special surface roughness patterns to an impingement surface to improve the effectiveness of impingement cooling. This investigation utilizes various sizes, distributions, shapes, and patterns of surface roughness elements for impingement cooling augmentation. Surface roughness shapes include rectangles, triangles, and cylinders. Combinations of small roughness and large pins are considered. Tests are performed at Reynolds numbers of 900, 1500, 5000, and 11000. In general, plates with small roughness alone perform better than plates with a combination of small roughness and large pins at Reynolds numbers of 900 and 1500. Combinations of small rectangle roughness and large pins give better heat transfer results than the small rectangle roughness alone at Reynolds numbers of 5000 and 11000, while the triangle roughness and cylinder roughness configurations with large pins show little improvement over small roughness alone. All triangle roughness configurations perform better than the rectangle configurations.
Buzzard, Warren, "Influences of target surface roughness on impingement jet array heat transfer" (2015). Theses. 146.