Experimental and Computational Analysis of Heat Transfer Enhancement Using Plain and Modified Tape Inserts

Abstract

The efficiency of heat exchangers is critical in applications ranging from process industries and power plants to HVAC systems and spacecraft. Heat transfer augmentation techniques aim to increase the heat transfer coefficient without substantially increasing pumping power or system size. This paper presents an experimental and computational study of heat transfer enhancement in concentric tube heat exchangers using plain tape and modified tape inserts (step cut arc, step cut rectangle and horizontal wing designs). Various flow regimes were tested and thermal performance was evaluated using Nusselt numbers, friction factors and thermal enhancement factors. Computational Fluid Dynamics (CFD) modelling was employed for validation. Results indicate that modified inserts significantly improve heat transfer compared to plain tubes, with the PT-HW configuration showing the highest thermal enhancement, especially in turbulent flow. Findings offer insights into designing compact and energy-efficient heat exchangers.