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This paper presents a methodology developed using Design of Experiments to predict the maximum temperature of an automotive headlamp reflector for the given geometry of the headlamp components and heat source. The proposed approach has been validated through comparison with three-dimensional Computational Fluid Dynamics simulation. The final out come of this study is a set of transfer functions, which can predict the maximum temperature of a reflector, positioned either in horizontal or vertical configuration.

The thermal performance of an automotive forward-lighting assembly is predicted with a computational fluid-dynamics (CFD) program. A three-dimensional, steady-state heat-transfer model seeks to account for convection and radiation within the enclosure, conduction through the thermoplastic walls and lens, and external convection and radiation losses. The predicted temperatures agree well with experimental thermocouple and infrared data on the housing. Driven by the thermal expansion of the air near the bulb surface, counter-rotating recirculation zones are predicted within the enclosure. The highest temperatures in the plastic components are predicted on the inner surface of the shelf above the bulb where airflow rising from the hot bulb surface impinges.

This paper introduces two new types of basic components (an Electro-Hydraulic Tube and a Hydraulic Tube) which when connected in an appropriate manner can control flow and pressure for many applications; in addition, one of the devices is readily interfacable to a microprocessor for external control. Some background information about the basic concept and the operation of the two components is introduced. Some of the experimental characteristics will be illustrated and several basic circuit examples will be presented to show how the concept can be implemented. The Electro-Hydraulic Integrated Block (EHIB) and Circuit (EHIC) will be introduced followed by a discussion of the advantages and potential of the EHIC concept.

The objective of this paper is to list some of the parameters involved in choosing a microprocessor for a particular application and to discuss some of the interrelationships between these parameters. The most important parameters are those depending on the application such as the number of inputs, number of outputs, required throughput, type of interfaces, and the total number of systems to be produced. Another set of parameters is microprocessor dependent such as the instruction set, throughput, and hardware and software support. Finally, parameters related to in house hardware and software expertise must be considered.