Experimental study of heat transfer parameters of impingement heating system represented by conductive target plate of resistive film

• Published in: Engineering and Technology Journal Vol. 34; no. 8A; pp. 1588 - 1604
• Main Authors: Yusuf, Asim H., al-Dabbagh, Amir M., Aun, Salah H. Abd
• Format: Journal Article
• Language: English
• Published: Baghdad, Iraq University of Technology 01.08.2016; Unviversity of Technology- Iraq
• Subjects: cooling effectiveness; discharge coefficient; jet impingement; nusselt number
• ISSN: 1681-6900; 2412-0758
• DOI: 10.30684/etj.34.8A.10

The current experimental study focuses on the heat transfer characteristics and pressure losses for impingement system which is used in cooling the liner of gas turbine combustor. Recent experiment method of conductive heat transfer technique with resistive film in the back side target plate is introduced. The present experimental model measured both the heat transfer coefficient for inner target surface and the wall cooling effectiveness for outer target surface. To physically explain the phenomena associated with interaction flow area, a computational fluid dynamic code (Fluent 14) is employed. The continuity, momentum and energy equations are computationally solved to analyze the flow field in the jet impingement area. The tests models of the impingement plate are made from round jet holes of inline and staggered arrays arrangement with jet to jet spacing of four-hole diameter. Jet Reynolds numbers of 4200 to 15000 and jet height to diameter ratio of 1.5, 2.0, and 3.0 are maintained. The inline array, as expected enhanced the wall cooling effectiveness over that of the staggered array by 10.3% and both jet spacing and Reynolds number have an evident effect on the discharge coefficient. Empirical correlations are obtained for both arrays arrangement to predict the area-averaged Nusselt number as a function of jet governing parameters.