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A theoretical model is proposed to study the fluid flow and heat transfer behavior of two dimensional impinging jet on a solid surface. Energy integral method is used to obtain the solution. Based on the analysis a generalized expression involving various modelling parameter such as Nusselt number, nozzle to plate distance, Prandtl number, Reynolds number and the modelling parameter k is obtained. Experimental investigation is performed to evaluate the heat transfer characteristics of a two dimensional impinging jets on the hot foil. Tests have been carried by using a two dimensional nozzle with length to diameter ( l/d h ) ratio of 70. Reynolds number based on nozzle exit condition is varied between 7000 and 17 000 and jet-to-plate spacing between 1 and 10. A hot foil of 0.15 mm (SS 304) is used as the test specimen and air is used as fluid during experiments. The local heat transfer characteristics are estimated from the thermal images obtained from infrared thermal imaging camera (A655sc, FLIR System). The results obtained from the theoretical model are compared with test data obtained during present experimental investigation. In addition, a correlation for Nusselt number is proposed as a function of nozzle to plate distance, Prandtl number, Reynolds number, radial distance. [ABSTRACT FROM AUTHOR]

A theoretical model is proposed to evaluate the heat transfer characteristics of axisymmetric impinging fluid jets on the horizontal hot surface in the stagnation region using the energy integral method. A generalized expression involving various modeling parameters such as Nusselt number, nozzle-to-plate distance, Prandtl number, Reynolds number, and the modeling parameter k is obtained from the analysis. Present predictions are found to agree well with the test data involving a wide range of coolant type, Reynolds number, and nozzle-to-plate distance. In addition, a mechanistic correlation is suggested between the modeling parameter k and flow parameter, i.e., Reynolds number. [ABSTRACT FROM AUTHOR]