Experimental and Numerical Analysis of Shell-and-Tube Heat Exchangers for Heat Transfer Education

The present study investigates heat transfer in a small parallel-flow shell-and-tube heat exchanger through experimental and numerical approaches. Experimental measurements were carried out on a dedicated test bench. The three-dimensional flow is modeled using the incompressible, single-phase Navier–Stokes and energy equations. For the discretization of the transport equations, we used the ANSYS Fluent 2025 calculation code, specifically the student version, which employs the finite volume method. In this work, we simulated different configurations, choosing three flow rates for the hot fluid (Vh = 1.4, 2, 2.5 L/min) and a fixed flow rate of 1.4 L/min for the cold fluid in all three cases. The simulation results closely match the experimental results. Increasing the hot water flow rate improves heat transfer between the two fluids, consequently enhancing and increasing the overall thermal efficiency. This study aims to consolidate our students' knowledge of the numerical analysis of a shell-and-tube heat exchanger, compare the results with experimental data, and perform visualization analyses of the flow within the tubes and the shell. Correlation-based methods can signal the presence of a design flaw, but CFD simulations are also capable of determining the origin and location of that flaw.