Numerical Study of Heat Exchanger Having Protrusion and Dimple Roughened Conical Ring Inserts

Abstract

Heat transfer rate augmentation in heat exchangers with least pressure drop is one of the important fields for research in research fraternity. The different types of inserts have been used in the tube to fulfill the objective. In the present model, a conical-ring turbulators with protrusion and dimple roughness from inside has been used as an insert. These turbulators were placed inside the heat exchanger tube, and tube was applied with uniform heat flux condition. A parametric study has been performed for different diameter (3, 6 and 9 mm) and pitch space (60 and 240 mm) of protrusion and dimple. The Reynolds number has been varied from 5000–30,000, and heat flux of 1200 W/m2 was used. It was concluded that as pitch space and Reynolds number increases, Nusselt number also increases. The protrusion shaped roughness has better thermal performance factor than dimple shape. The diameter of 6 mm has performed better than 3 and 9 mm for both the cases of roughness.