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Development of new passenger-car climate control systems that contribute to improved comfort and decreased fuel consumption requires quantitative evaluations of thermal sensation and comfort. Therefore, a new evaluation method of the transient and non-uniform passenger-compartment thermal environment has been developed. Vehicle occupant's local thermal sensations are evaluated by using the local standard new effective temperature (SET*) that is calculated using a human thermoregulation model. The occupant's whole-body thermal comfort is then evaluated by local thermal sensation. The theory of the method and some example application results are introduced in this paper.

Accuracy of numerical simulation has to be evaluated through the actual phenomenon such as experiment or measurement and then it can be employed to design the air-conditioning system of car cabin at the development phase. Scaled model of vehicle cabin was created by the Society of Automotive Engineers of Japan (JSAE) and the experiment was performed to obtain the detailed information of heat transfer characteristics inside the cabin under the non-isothermal condition. The sheet heaters were put to the inner surface of the acrylic cabin and they supplied certain amount of heat. The temperatures of inner and outer surface and air were measured to evaluate the thermal environment of the cabin. The results lead to enhancement of the data of the standard model of the cabin.

Diesel injection equipment is required to be more accurate and higher in pressure to meet the increasingly strict emission, fuel consumption regulations and higher engine performance. It also needs to achieve a number of requirements such as robustness against diversified market fuels, easy installation to engine, etc.

The demand for high efficiency powertrains in automotive engineering is further increasing, with hybrid powertrains being a feasible option to cope with new legislations. So far hybridization has only played a minor role for L-category vehicles. Focusing on an exemplary high-power L-category on-road vehicle, this research aims to show a new development approach, which combines longitudinal dynamic simulation (LDS) with “Design of Experiments” (DoE) in course of hybrid electric powertrain development. Furthermore, addressing the technological aspect, this paper points out how such a vehicle can benefit from 48V-hybridization of its already existing internal combustion powertrain. A fully parametric LDS model is built in Matlab/Simulink, with exchangeable powertrain components and an adaptable hybrid operation strategy. Beforehand, characterizing decisions as to focus on 48V and on parallel hybrid architecture are made.

In a high gas velocity condition in cylinder, the ground electrode orientation of the spark plug causes the ignitability to fluctuate due to the change in gas flow around the spark gap. As one method to solve this issue we have focused on controlling the gas flow by plate like airfoils or turbine blades. We have developed gas flow control technology for the spark plug to achieve high ignitability under the worst case condition of ground electrode orientation. The adoption of current ground electrode welding technology has allowed us to locate a flow guide plate on the plug housing.

Vehicle electronics systems will continue to become more complex and larger in scale. This causes their development to be conducted without control. As a result, system development involves things becoming intertwined with each other, like spaghetti. This has made it extremely difficult to develop an entire electronics system coherently and efficiently, from functional architecture down to physical architecture. There is thus a need to reform the development style of the electronics field to a style which will continuously and efficiently generate high-quality products. This will be achieved by dividing development into functions and components. Function development refer to developing functions that OEMs want to equip in the vehicles, that is, “what to make. Components development refers to “how to realize these components. For this activity, it is necessary to promote and accelerate platform-based development looking down at entire electronics systems.

DiMethyl Ether (DME) has been known to be an outstanding fuel for combustion in diesel cycle engines for nearly twenty years. DME has a vapour pressure of approximately 0.5MPa at ambient temperature (293K), thus it requires pressurized fuel systems to keep it in liquid state which are similar to those for Liquefied Petroleum Gas (mixtures of propane and butane). The high vapour pressure of DME permits the possibility to optimize the fuel injection characteristic of direct injection diesel engines in order to achieve a fast evaporation and mixing with the charged gas in the combustion chamber, even at moderate fuel injection pressures. To understand the interrelation between the fuel flow inside the nozzle spray holes tests were carried out using 2D optically accessed nozzles coupled with modelling approaches for the fuel flow, cavitation, evaporation and the gas dynamics of 2-phase (liquid and gas) flows.

Dimethyl ether (DME) is a promising alternative fuel for compression ignition (CI) engines. DME features good auto ignition characteristics and soot-free combustion. In order to develop an injection system suitable for DME, it is necessary to understand its fuel properties. Sound speed is an important fuel property that affects the injection characteristics. However, the measurement data under high-pressures corresponding to those in fuel injection systems are lacking. The critical temperature of DME is lower than that of diesel fuel, and is close to the injection condition. It is important to understand the behavior of the sound speed around the critical point, since the sound speed at critical point is extremely low. In this study, sound speed in DME in a wide pressure and temperature range of 1 MPa to 80 MPa, 298.15 K to 413.15 K, including the vicinity of the critical point, was measured. The sound speed in DME decreases as either the pressure falls or the temperature rises.