Jet impingement cooling of a discretely heated portion of a protruding pedestal with a single round air jet

Abstract The influence of a protruding pedestal on impinging jet heat transfer is investigated. A discretely heated portion of a protruding pedestal is exposed to a single circular impinging air jet with Re =10,000–30,000. Jet exit diameters of 3.5, 9.5 and 21 mm are positioned at jet exit-to-surface distances of 2–5 diameters. The nondimensional heat transfer over the discretely heated portion of the pedestal is compared to a flat plate design to gauge the effects of Reynolds number, jet diameter and jet exit-surface spacing. In all cases, the presence of the protruding pedestal downstream is found to increase heat transfer.

[1]  Raymond E. Chupp,et al.  Evaluation of internal heat-transfer coefficients for impingement-cooled turbine airfoils. , 1969 .

[2]  Chie Gau,et al.  Surface Curvature Effect on Slot-Air-Jet Impingement Cooling Flow and Heat Transfer Process , 1991 .

[3]  W. Aung,et al.  Cooling Technology for Electronic Equipment , 1988 .

[4]  T. Igarashi,et al.  Heat transfer from a square prism to an air stream , 1985 .

[5]  P. Hrycak.  Heat transfer from a row of jets impinging on concave semi-cylindrical surface , 1978 .

[6]  H. Martin.  Heat and Mass Transfer between Impinging Gas Jets and Solid Surfaces , 1977 .

[7]  H. A. El-Sheikh,et al.  Enhancement of air jet impingement heat transfer using pin-fin heat sinks , 2000 .

[8]  D. E. Metzger,et al.  Impingement Cooling of Concave Surfaces With Lines of Circular Air Jets , 1969 .

[9]  Y. Chung,et al.  Turbulent flow and heat transfer measurements on a curved surface with a fully developed round impinging jet , 1997 .

[10]  Masud Behnia,et al.  Predictions of turbulent heat transfer in an axisymmetric jet impinging on a heated pedestal , 1999 .

[11]  R. Viskanta.  Heat transfer to impinging isothermal gas and flame jets , 1993 .

[12]  B. L. Button,et al.  A review of heat transfer data for single circular jet impingement , 1992 .

[13]  R. Goldstein,et al.  Jet impingement cooling of a convex semi-cylindrical surface , 2001 .

[14]  J. P. Hartnett,et al.  Advances in Heat Transfer , 2003 .

[15]  H. Schlichting.  Boundary Layer Theory , 1955 .

[16]  Thomas A. Trabold,et al.  Impingement Heat Transfer Within Arrays of Circular Jets: Part 1—Effects of Minimum, Intermediate, and Complete Crossflow for Small and Large Spacings , 1987 .

[17]  Richard J Goldstein,et al.  Flow visualization of a round jet impinging on cylindrical surfaces , 1999 .