Evaluation of Equivalent Temperature in Vehicle Cabin by a Mesh-Free Simulation—Part 3: Evaluation of Equivalent Temperature under Transient Heating Condition 2022-01-0192

This paper describes the equivalent temperature based on the mesh-free simulation proposed by the previous papers (Part1 and Part2) under the transient heating condition in a 3D-CAD vehicle cabin including the thermal manikin which takes into account the clothing shape. For this purpose, firstly, the experiments of vehicle cabin measuring for the thermal environment including the equivalent temperature are carried out under the transient heating condition. Then, the calculated results of the thermal environment in the vehicle cabin are compared with time series experimental data under the transient condition. They correspond to the experiments including transient changes well. The transient calculated equivalent temperature of thermal manikin is also compared with experiments. As a result, since it is difficult to control the thermal manikin ideally in the experiment, it is difficult to compare the transient behavior. In particular, it is difficult to measure the amount of heat loss from the thermal manikin at the early stage of transient heating in the experiment. On the other hand, in the analysis, the thermal manikin can be controlled ideally so that the equivalent temperature can be evaluated including the transient condition. In this way, some differences between the actual phenomenon and the ideal situation can be confirmed under the transient behavior of the thermal manikin. Furthermore, effects of heat capacity of the clothing on the equivalent temperature are also studied. The behavior of the equivalent temperature calculated by the three types of setting methods for the heat capacity is different on the body segment of the thermal manikin of which heat capacity is large at the early stage of transient heating.