Numerical Simulation of the Performance of a Sudden Expansion With Fence Viewed as a Diffuser in Low Reynolds Number Regime

In this paper, the results of numerical simulation on the performance of a sudden expansion with fence viewed as a diffuser are presented. The two-dimensional steady differential equations for conservation of mass and momentum have been solved using the semi-implicit method for pressure-linked equations (SIMPLE) algorithm. The Reynolds number is in the range of 20–100 and fence subtended angle (FSA) between 10 deg and 30 deg. An aspect ratio of 2 is fixed for all the computations. The effect of each variable on average static pressure and diffuser effectiveness has been studied. Computations have revealed that for higher Reynolds number, the use of a fence always increases the effectiveness of the diffusion process when compared with a simple sudden expansion configuration. In low Reynolds number regime, depending on the positioning of the fence and the fence subtended angle, the fence may increase or decrease the diffuser effectiveness in comparison with sudden expansion without fence.