The purpose of this research paper is to investigate the effect of surface roughness on heat transfer. This was achieved by investigating the heat transfer in two cases: a smooth, horizontal surface (the baseline case) and the same surface with a roughness element added to it. The roughness elements took the shape of hemispherical pin-fin. The roughness element was further investigated by varying its height and width (e by e) to study their impact on the average Nu. Results are presented in the form of average Nusselt number within and beyond the stagnation region. Each roughness element was arranged in a circle concentric with the geometric centre (i.e. centre of jet) with a radius of one and a half jet diameters (R/D = 1.5) to keep it within the stagnation region. The jet diameter kept constant for all simulations (D=13.5mm) where the plane was located at H/D = 6 below the jet, for all the tests with a jet Reynolds number of 20,000 and jet temperature is 20°. The spherical pin-fin was tested for six different heights (e) from 0.25 mm to 1.50 mm in incremental steps of 0.25 mm for jet angle (α) of 90°. This research investigated how the roughness geometry impacted on the average Nusselt number.


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    Title :

    Heat transfer characteristics of an orthogonal jet impinging on roughened flat plate




    Publication date :

    2017-07-01


    Size :

    538605 byte




    Type of media :

    Conference paper


    Type of material :

    Electronic Resource


    Language :

    English



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    Jet Impingement Heat Transfer Enhancement on a Rib-Roughened Flat Plate (AIAA 2016-0241)

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