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With development of high grade and high performance vehicles, there's a growing demand for improvement of thermal comfort in the car. Such comfort is evaluated by the passenger's thermal sensations, such as “hot” or “cold”. For improvement, we need to develop an air conditioning system which can reflect the passenger's sensory feelings as a thermal sensation. In part 1, we described thermal sensation of a passenger in a car depends on not only the skin temperature, but also the rate of change of the skin temperature, and we propose a thermal sensation evaluating equation. For this paper, we used this equation to replace the thermal sensation with the skin temperature, and studied a system which reflects the thermal sensations through on air conditioning control based on the skin temperature. We also verified the advantages of the system under various thermal conditions.

The purpose of this study is to present a new method for controlling a car air conditioning system, in which the air temperature can be controlled to produce any level of occupants' thermal sensation by utilizing car occupants' skin temperatures as a controlling index. In this paper, an equation for a quantitative evaluation of car occupants' thermal sensation, in steady and non-steady states, by face skin temperature and its rate of change was developed and was confirmed by experiments in an environmental chamber to be applicable for all seasons with an accuracy of ±1 in the thermal sensation voting scale we used.

The objects of this work is to develop a method of evaluating the thermal sensation of an automobile occupant and predicting its transition for the development of a new control system for automobile air-conditioners. An automobile air-conditioner is designed only to control the air-temperature of a passenger compartment. However, The most important factor in controlling automobile air-conditioner is the thermal amenity for occupants when an air-conditioner is controlled. For the control of the thermal amenity, it is necessary to quantitatively evaluate the thermal sensation of occupants. This paper presents a new method using neural networks, which was developed to evaluate the thermal sensation of an automobile occupant and to predict its transition from the occupant's skin temperature and temperature of the passenger compartment. Experiments were performed in an environmental chamber.

Regeneration experiments were carried out for the establishment of a particulate combustion model. Distributions of the filter temperature and gas temperature, the concentration of the oxygen in the filter, and combustion products were simultaneously measurd. Numerical simulations were performed by two steps. As the first step, a quasi one-dimensional simulation model was applied to the estimation of propagation characteristics of the particulate combustion, such as flame velocities, and the filter temperature change with time. Air velocity and heat capacity of the filter were found to be important factors for the combustion propagation. As the second step, a two-dimensional axisymmetric simulation program for the regenerative combustion was developed and coupled with a FEM stress analysis program “MARC”.

Regeneration capability of a wall-flow monolith type diesel paticulates filter with an electric heater was studied. To prevent filter crack generation and unburned particulates accumulation, a precision controller was added to the test equipment to reduce thermal load. In order to control the supply of oxygen to potentially prevent cracking, a second air feeder was also added. Furthermore, to ignite the accumulated particulates uniformly and propagate extensively to burn accumulated particulates completely a newly improved heater unit was employed. Repeated regeneration tests were conducted with cars on a chassis dynamometer. Though crack generation and unburned particulates accumulation were reduced considerably, satisfactory prevention could not be achieved. Therefore a parameter study using regenerative burning and thermal stress analysis model was carried out.

A prediction technique for the lubricating oil temperature in a manual transaxle was developed. Using this technique, the effects of heat transfer enhancement and heat generation decrease, etc., on the oil temperature reduction can be estimated. The heat generation in a manual transaxle is caused by lubricating oil stirring, friction and gear meshing. The heat transfer and flow characteristics are thus very complicated under the two-phase flow of the oil and air induced by rotating gears. It is necessary for the development of the prediction technique to model the heat transfer process in a manual transaxle. The experiments measuring of heat generation, heat flux and the air flow velocity distribution around the manual transaxle were conducted to get information for modeling the heat transfer process. A flow visualization of two-phase flow in the manual transaxle was also conducted.