Title：Double wall cooling of a full coverage effusion plate with main flow pressure gradient and different internal cooling supply arrangements

Reporter：Phil Ligrani

University of Alabama in Huntsville

Time：9:30am，Sept. 19th, 2018（Wednesday）

Site：A-559, Lee Shau Kee Building of Science and Technology

Inviter：Prof. Jing Ren (任静 教授)

Abstract：

Experimentally measured results are presented for different experimental conditions for a test plate with double wall cooling, comprised of full-coverage effusion-cooling on the hot-side of the plate, and different cooling arrangements on the cold-side of the plate. Different coolant supply arrangements include cross-flow only, impingement only, and combinations of cross-flow and impingement together. The results presented are different from those from past investigations, because of the addition of a significant mainstream pressure gradient, and because of the unique coolant supply configurations. Main stream flow is provided along a passage with a contraction ratio of 4, given by the ratio upstream flow area, to downstream flow area. With this arrangement, local blowing ratio decreases significantly with streamwise development along the test section, for every value of initial blowing ratio considered, where this initial value is determined at the most upstream row of effusion holes. Experimental data are given for a sparse effusion hole array. The experimental results are provided for mainstream Reynolds numbers of 92400 to 96600, and from 128400 to 135000, and initial blowing ratios of 3.3-3.6, 4.4, 5.2, 6.1-6.3, and 7.3-7.4. Results illustrate the effects of blowing ratio for the hot-side and the cold-side of the effusion plate. Of particular interest are values of line-averaged film cooling effectiveness and line-averaged heat transfer coefficient, which are generally different for contraction ratio of 4, compared to a contraction ratio of 1, because of different amounts and concentrations of effusion coolant near the test surface. In regard to cold-side measurements on the crossflow side of the effusion plate, line-averaged Nusselt numbers for contraction ratio 4 are often less than values for contraction ratio 1, when compared at the same main flow Reynolds number, initial blowing ratio, and streamwise location.

Brief Biography:

Dr. Phil Ligrani is currently the Eminent Scholar in Propulsion, and Professor of Mechanical and Aerospace Engineering at the University of Alabama in Huntsville. Previously, he was the Oliver L. Parks Endowed Chair, and Professor of Aerospace and Mechanical Engineering at Parks College of Saint Louis University. His prior academic position was as the Donald Schultz Professor of Turbomachinery in the Department of Engineering Science at the University of Oxford. There, from 2006 to 2009, he was also Director of Oxford University’s Rolls-Royce UTC (University Technology Centre) in Heat Transfer and Aerodynamics. As of August 2018, Dr. Ligrani is author or co-author of more than 181 publications in archival journals, 9 book chapters, as well as approximately 132 conference publications and presentations. From 2010 to 2018, he presented or is scheduled to present 5 Invited Keynote Papers, 8 Invited Papers, and 5 Invited Plenary Keynote Papers at different international conferences. He has been primary advisor for a total of 94 graduate students completing Ph.D., M.E., M.S. degrees, and Turbomachinery Diplomas. Research interests include turbomachinery, convective heat transfer, and fluid mechanics, as well as micro-fluidics, fractionation, and measurement technologies.

Some of his recent honors, awards, and academic recognitions include:

● Outstanding Mechanical Engineer of the Year Award 2016, ASME – American Society of Mechanical Engineers, NAS - North Alabama Section, USA.

● Distinguished Advisory Professor, Inje University, South Korea, 2010 to 2018.

● Distinguished Lecture Award, 2011, CEAS Distinguished Lecture Series, College of Engineering, University of Wisconsin, Milwaukee, Wisconsin, USA.

● Distinguished Editorial Review Board membership for Springer Publishing Corporation.

● Carl E. and Jessie W. Menneken Faculty Award for Excellence in Scientific Research.

● NASA Space Act Tech Brief Award for "Development of Subminiature Multi-Sensor Hot-Wire Probes."

● Silver Winner for the Annual 26th Educational Advertising Awards for the Higher Education Marketing Report.