Experimental and CFD simulation study of shell and tube heat exchangers with different baffle segment configurations

Abstract

Sell and tube heat exchanger (STHX) is an implement that has tremendous applications in numerous industrial processes and research areas. In this study, the commercial software ANSYS is used for 3-D CFD to compare the thermo-hydraulic performance of STHX with recently developed tri-angular (TRI) baffles, and tri-flower (TF) baffles with conventional segmental (SG) baffles at different flow rates. Simulations have been performed to analyze the heat transfer coefficient, pressure drop, and overall thermo-hydraulic performance among the recently developed TRI-STHX, TF-STHX and conventional SG-STHX. The thermo-hydraulic performance of the numerical model of SG-STHX shows the promising results while validating it with the experimental results, Esso and Kern methods. Then the same study is carried out for comparing the two novel baffles with segmental baffle. The results depict that, novel baffles are much appreciable in increasing heat transfer coefficient. The TF-STHX offers a greater heat transfer coefficient than all others but also offers a higher pressure drop at the same flow rate. Computing the comprehensive performance, hs??p, the TRI-STHX offers a prominent increment in thermo-hydraulic performance compared to others. Moreover by inserting twist?ed tapes at the tube side, there is noticeable increase in heat transfer coefficient which tends to increase the thermo-hydraulic performance of STHX. By comparing the flow patterns of TRI-STHX and SG-STHX, the novel TRI-STHX shows the reduction in shell-side induced vibrations and hence helped to increase the overall efficiency of the STHX.