Development and Validation of an Open-Source MATLAB Simulation Model for Shell-and-Tube Heat Exchanger Performance in Aerospace Waste Heat Recovery

This study presents the development and validation of a MATLAB1-based simulation model for evaluating the thermal performance of a shell-and-tube heat exchanger in waste heat recovery for aerospace applications. The model can estimate water heat transfer properties through a built-in numerical model, allowing the simulation of the Nusselt number and convection heat transfer coefficient. Key decision variables, such as the overall heat transfer coefficient, the number of transfer units (NTU), and heat exchanger effectiveness, are incorporated to predict the system’s performance under varying hot-side temperature conditions while maintaining constant cold-side parameters. The simulation focuses on two primary metrics: the waste heat captured by the cold fluid and the outlet temperature of the cold fluid. Experimental validation was conducted in a controlled laboratory environment with a counter-flow heat exchanger using water as the working fluid. Inlet and outlet temperatures, mass flow rates, and ambient conditions were measured using calibrated sensors. The results demonstrated a high correlation between experimental and simulation data, with the Mean Absolute Error (MAE) for temperature and waste heat being 2.29°C and 149 W, respectively, and the Root Mean Square Error (RMSE) values being 2.51°C for temperature and 166 W for waste heat. These findings confirm the model’s accuracy and reliability in predicting the thermal performance of shell-and-tube heat exchangers for aerospace waste heat recovery. Future work includes integrating open-source models for flat plate and tube-in-tube heat exchangers to enhance further waste heat recovery in aerospace applications under varying waste heat quality.