Abstract:

Simulations can be a useful learning resource to improve the technical competencies of industrial engineering students. Computational fluid dynamics (CFD) is an important simulation tool that provides detailed information about the heat flux through fluids, such as the temperature distribution and flow pattern in industrial equipment and processes. Due to the development of commercial CFD software and the continuous and rapid increase in the computing power of computers, CFD is a useful instrument for industrial engineers. The teaching of CFD in engineering subjects is usually based on the study of the numerical methods they use and on the introduction of a CFD software as a virtual reality laboratory but without paying attention to the use of commercial software. At the School of Engineering of the University of Almeria, the use of CFD has been introduced in practical classes of the subject of Thermal Engineering to analyse two practical cases of heat transfer in heat exchangers. This subject corresponds to the second year of four different degrees in the industrial field: in Mechanical Engineering, in Industrial Electronic and Automatic Engineering, in Electrical Engineering and in Industrial Chemical Engineering. In this work, we proposed the use of CFD simulation to analyse a shell and tube heat exchanger working with water and an aluminium fin heatsink cooled by ambient air. In both cases, the fundamentals of heat transfer and fluid flow were studied previously to help students understand the CFD process, interpret and validate the simulation results. CFD models were developed using the ANSYS/FLUENT software, since students have free access to the Ansys Student version. The results of the CFD simulations were compared with the analytical results calculated by the students and with the results obtained using a second simulation tool developed in Microsoft Excel in a previous experience of teaching innovation. The main utility of CFD is the ability to visualize the flow pattern of transparent fluids such as water and air, helping students understand how their movement contributes to heat exchange. The visualization of velocity vectors using CFD simulations also allows students to comprehend the difference between natural convection (produced in the heatsink) and forced convection (generated by the water supply in the multitube heat exchanger). Similarly, CFD simulations make it easy to modify fluid velocities from laminar to turbulent and check the effect of the flow regime on heat transfer. It is also simple to modify the material of the tubes or fins that exchanges heat with the fluid in the simulations to see how it affects the thermal power exchanged. The general perception of the students was that the CFD simulations helped them to better understand the operation of the two heat exchange systems. The statistical results show a good acceptance in terms of learning, reflection, motivation, and satisfaction. Most of the students showed their interest in learning how the software works, they would like courses to be taught for their learning in the degree.

Keywords:

Computational Fluid Dynamic (CFD), simulation tools, teaching-learning, engineering education, conduction-convection heat transfer.