Heating Load Characteristics of a Passenger Car

Abstract

Heating characteristics of passenger car are determined not only by those of the body itself, but also those of radiator for room temperature, wall radiation characteristics, number of passengers and ventilating air volume. Especially, in the running state, boundary conditions in-and out-doors are very changeable and, moreover, in the case of preheating, the room temperature has to be raised to a necessary degree in a short time. On the contrary, if the heating quantity is too much, the passenger feels very uncomfortable. For this reason, we must control the room temperature considering the wall temperature as well as the change of outdoor temperature. For heating load estimation of the car, we cannot get proper quantity by the steady state heat estimation alone. In such case, heat capacities of car itstelf and room equipments are very important factors. The author carried out many tests on a passenger car of J.N.R. (SUHA-439). In this paper some estimation data obtained from these tests are reported as follows.