International Journal of Engineering Research in Electronics and Communication Engineering

Experimental Techniques to Control Flow Structure in Sudden Expansion Geometry

Author : K.Ashokachary ¹ S.Manikanthachary ² V.Rajarao ³

Date of Publication :7th August 2016

Abstract: Reduction in recirculation zone size in suddenly expanded geometries is one of the major issues to deal with. After the flow encountering the sudden expansion geometry it gets many complex features like separation, recirculation, attachment and reverse flow. In the present study, flow over such geometries with blowing and suction scenario are studied for differentLmax/Lminmodels namely 3, 4 and 5.It is found that for Lmax/Lmin= 5 the re-circulation and loss zones are more, for further studying Lmax/Lmin= 5 is subjected to different operating conditions like with blowing and suction. For further improvement the blowing is studied at different heads of pressure like 200 mm and 300 mm of water. With suction flow scenario is completely changed and attachment point is observed at the base of the model itself. Results thus identify the improved flow structure

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