Teaching heat exchanger design using COMSOL Multiphysics in a computer-based lab

Abstract

The operation of a heat exchanger is a multiphysics problem, involving the simultaneous flow of two fluids and heat transfer between them. Velocity, pressure and temperature gradients within each fluid vary with location, operating conditions, flow arrangement and heat exchanger geometry. While robust design procedures exist, including analytical approaches, their solution can be hard to fully comprehend without computational tools that visualize the underlying physical processes within the heat exchanger. Here, we present a classroom exercise aimed at improving student’s understanding of double pipe heat exchangers using the computational fluid dynamics software COMSOL Multiphysics. This computer-based laboratory class is integrated within a ‘Process Heat Transfer’ module offered to undergraduate and postgraduate chemical engineering students. The exercise is fully documented, including the problem statement and solution, and guides students to apply the design workflow and discuss their solutions in class. A survey distributed at the end of the module indicates overall satisfaction with the hands-on approach, especially the opportunity to receive training on a computational software. A pre- and post-test evaluation demonstrates that the computer-based class helped eliminate persistent student misconceptions regarding the operation of heat exchangers. Ensuring proper software set-up, in-class support, and the provision of instructional material is crucial due to the learning curve associated with using the software. By developing a digital model of the heat exchanger, the exercise serves as a cognitive tool—encouraging students to explore more advanced problems, such as the completion of parametric studies, thereby reinforcing the understanding of theoretical concepts.