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Electromagnetic compatibility (EMC) is becoming more important in power converters and motor drives as seen in hybrid electric vehicles (HEV) to achieve higher reliability of the vehicle and its components. Electromagnetic interference (EMI) of the electronic components for a vehicle are evaluated and validated at a component-level test bench; however, it is sometimes observed that the EMI level of the components can be changed in a vehicle-level test due to differences in the vehicle's configuration (cable routing, connecting location etc.). In this presentation, a vehicle-level EMC simulation methodology is introduced to estimate radiated emissions from a vehicle. The comparison between the simulation and measurement results is also presented and discussed.

In this work, the flow velocity distribution was determined by measurements of visualized flow, obtained with a one-fourth scale three-dimensional model, and by numerical analysis. The measurements of interior flow were obtained using a method which combined the particle-tracking technique, a basic method conventionally employed for flow visualization, with a pulsed-laser-light-sheet technique. Flow images taken with a video camera were then processed by means of an image processing system. Flow velocity distributions were obtained for two different discharge modes - a dashboard-vent mode in which air was discharged from four vents provided along the top of the dashboard, and a bi-level mode in which vents at the foot position were added to those of the first mode. Three-dimensional numerical analyses using a direct-simulation method were conducted to calculate the interior flow, and a comparison was made with the measured results obtained in the visualization experiment.

As the use of automobiles spreads throughout the world, not only the ratio of car air conditioner use but also in the regions in which they are used is increasing. Therefore, the car air conditioner must now be durable enough to withstand many widely different environments. This paper reports our findings on air conditioner cycle movement in relation to the amount of refrigerant used. It also establishes a protective system against the failure mode under each of the various environments. In particular, an automatic sensing device is introduced which tells the proper refrigerant level and guards against human error in gas charging.

Modern vehicles are expected to both be able to provide thermal comfort and to insure visibility for safe driving by preventing frost formation on the windows even at temperatures of below −20°C. Frost formation is the phenomenon resulting from breathed vapor which saturates along the inner surface of the windows at below 0°C and prevents the penetration of light from outside. To analyze the formation of frost on vehicle windows, the air flow in the compartment that controls the transfer of breathed vapor and the local air flow along the inner surface of the windows were observed using a herium bubble tracing method.