Numerical Analysis on Effect of Baffle Inclination Angle on Flow and Heat Transfer Characteristic of Shell and Tube Heat Exchanger with Helical Baffle

Abstract

In the present work numerical simulation is done to show effect of baffle inclination angle on thermal and hydraulic performance of shell and tube heat exchanger. For the said analysis a geometric similar model with 09 circular tubes in line arrangement is considered. The CAD model of the same is created using an unstructured Tetra/Hybrid mesh. Using finite volume method, steady flow momentum and energy equation are solved. Moreover, Renormalization Group (RNG) k-ε model is selected for the turbulent modeling. Simulations are carried out for ten different Reynolds number ranging 400≤ Re≤2200; three different Prandtl number between 0.7≤Pr≤118.2 and five different baffle angle between 200≤θb≤500. The methodology is validated with published experimental results and found to be in good agreement.

The results shows that, shell and tube heat exchanger with helical baffle producing more vortex flow and hence have higher heat transfer co-efficient and lower pressure drop as compared to the segmental baffle. The Simulation perform with various Reynolds numbers (Re), Prandtl numbers (Pr) and helical baffle inclination angle (θb) transformed into novel correlations for Nusselt number and Frictional factor. The correlations are developed based on multi variable regression analysis.

The simulation results shows that 500 helical baffle has 87.34% higher heat transfer co-efficient per unit pressure drop (Nu/f) as compare to segmental baffle heat exchanger.