Experimental Investigation of the Effect of Single and Twin Bluff Bodies on the Turbulent Flow in an Asymmetric Rectangular Diffuser

Abstract

Experimental investigation of the effect of bluff bodies on the turbulent flow through an asymmetric diffuser has been carried out. The rectangular diffuser is designed and made keeping similarity to that used by Buice and Eaton, [1], having an inclination angle of 10°. Three geometrical configurations have been selected for the experimentation. (I) At first the experiment has been carried out for the validation of the present results with Buice and Eaton, [1], placing no bluff body at all. (II) Thereafter measurements have been carried out by placing a single bluff body on the horizontal floor of the diffuser to estimate the effect of the bluff body on the downstream flow. (III) Finally, two identical bluff bodies are placed on the horizontal floor of the diffuser and experimental work has been carried out in order to investigate the effect of the existence of two bluff bodies on the downstream flow through the diffuser. The present results agree well with the results of Buice and Eaton, [1], to show that the recirculation zone appears just adjacent to the inclined plane when there is no bluff body in a diffuser. Also, the detailed investigation for velocity of flow field, distribution of skin friction factor along with uncertainty analysis as well as the correlation between friction factor and Reynolds Number have been carried out in the research paper.