CFD ANALYSIS AND ENHANCEMENT OF HEAT TRANSFER IN RECTANGULAR CHANNEL USING BLOCKAGE WITH ELONGATED HOLE

A model of channel with blockage designed and meshed in ALTAIR® HYPERMESH V.11 and used ALTAIR® ACUSOLVE for CFD analysis. The CFD analysis is validated by the experimental data. The rectangular channel has a width-to-height ratio of 11:1. The blockages are subdivided into two different cases using two different aspect ratios (hole-width-to-height ratio) which are determined by the number of holes with four and six holes per blockage. According to the results it is observed that at all Reynolds numbers, the h and Nu increases with increase in pitch ratio up to the value of 6.0 and then decreases with further increase in pitch ratio. This variation in h and Nu is due to flow reattachment downstream of the blockage’s opening and then redevelopment of boundary layer up to the succeeding next blockage’s opening. The blockages with shorter holes enhance heat transfer better than those with longer holes but they also yield significantly higher pressure drops than blockages with longer holes.