Thermal behaviour simulation of the passenger compartment of vehicles

In this work a calculus program developed with the objective of simulating the thermal behaviour in the passenger compartment of vehicles is presented. The model is based on the space-integral energy balance equations for the inside air and for the main vehicle body and surfaces. It can solve two kinds of problems. In the first one, it calculates the heat stress that the air conditioning system must equilibrate in order to satisfy predefined permanent regimen project specifications. In the second one, once imposed a particular air conditioning system and given the ambient conditions, it computes the different temperatures and heat fluxes, either in transient or steady regimens. The validation of this model was done with a railway car, in a summer situation, when it was immobilized and running. The model reproduced well the experimentally determined temperature and heat flux evolutions. However, the numeric simulation showed best agreement with the experimental results when used with the convection heat transfer coefficients, determined experimentally in this work