Helical baffle design in shell and tube type heat exchanger with CFD analysis

Abstract

In present day shell and tube heat exchanger is the most common type heat exchanger widely used in oil refinery and other large chemical process, because it suits high pressure application. The aim of this work is to design of shell and tube type heat exchanger with helical baffle and comparing with straight baffle with CFD analysis using ANSYS FLUINT software tools. The model contains 7 Copper tubes each having 20 mm external diameter and 17 mm internal diameter, length 600 mm and inner diameter of steel shell is 90 mm and outer diameter 110 mm. 7 tubes are hold by 6 straight or helical aluminium baffle and the helix angle of baffle is varying from 0° to 30°. All the models are design by using CATIA software tools. In this paper how the pressure drop and overall heat transfer coefficient varies due to different helix angle has been studied when the flow rate remain same. The flow pattern in the shell side of the heat exchanger with continuous helical baffles are forced to be rotational and helical due to the geometry of the continuous helical baffles, which results in a significant increase in heat transfer coefficient per unit pressure drop in the heat exchanger.