Abstract
Lately, very many people spend increasingly more time inside the automobile and for this reason there is a growing demand for systems to obtain an optimal thermal comfort. Thermal analysis of the passenger compartment involves not only geometric complexity, but also strong interactions between airflow and the three modes of heat transfer, namely, heat conduction, convection and thermal radiation. Since thermal comfort is a concept involving interior microclimate and human factors, its assessment must be made with thermal dummies. As costs for the tests are quite high, requiring thermal modeling and climatic wind tunnels, an alternative is represented by numerical simulation, whose cost is much lower compared to the cost of experiments. Another advantage is that the numerical simulation require less time for evaluation of the changes inside the model. The aim of this paper is to evaluate the thermal comfort inside the passenger’s compartment in two cases. The first case will be the standard case (single zone) and the second case will consist in adding two supplementary air vents for the rear passengers. The human thermal comfort evaluation will be done using the Theseus FE software, which has integrated a thermal manikin (Fiala’s manikin), necessary to calculate of the thermal comfort indices. The first part of the paper is the experimental setup. We will present the measurement methodology and the materials used, consisting in 12 thermocouples located in different parts of the passenger compartment, one acquisition system and one laptop PC. In the second part of the paper, we have realized the numerical simulation and the results obtained using the same boundary conditions as in the experimental research. The numerical simulation is realized using Ansys Fluent and Theseus FE software and for transfer data from one program to the other, we will use different Matlab journals. The obtained results will be compared with those obtained experimentally. Also, in the second part, we have evaluated the influence of positioning two supplementary air vents in the rear side of the vehicle. Those will be placed at the end of the central console. In terms of boundary conditions, we will keep the same flow rate as that used in the first computation. The obtained results will be compared with those for the first case.
Keywords: Numerical Simulation, Passenger Compartment, Computational Fluid Dynamics, Thermal Comfort, Theseus-FE