Optimization of the Heating System of a Bus Cabin: a Numerical Approach through OpenFOAM

Throughout human history, thermal comfort has been by far the most important factor when evaluating well-being. Although, there are numerous studies regarding thermal engineering in HVAC systems, their scope has primarily been focused on analyzing buildings or automobiles, but have barely fixated on buses. Moreover, in the field of computational fluid dynamics, there is virtually no research aimed towards this kind of vehicles. This thesis tries to fill this void by analyzing the heating system of a public transport bus in Turin, using the ASHRAE-55 standard, which is a guideline for thermal design in enclosed spaces. This work serves as a base reference for all the processes involving CFD simulations and thermal comfort analysis of a bus cabin. The first part covers everything from the retrieval of the bus geometry up to the post-processing of the output data. The second part consists of studying the minimum requirements for input thermal variables to ensure comfort during winter time in Turin. It concludes with the evaluation of the required amount of heat power needed to accomplish such task and the overall performance of the installed heating system. The outcome of this research is the improvement in heating efficiency of the bus without jeopardizing thermal perception on passengers.