Search Results

Eliminating on-road testing and replacing it with wind tunnel testing is an attractive alternative to become more efficient and lower development costs. However, depending on what type of testing is performed and where it is on the vehicle, wind tunnel testing may not agree with the on-road results. Site-to-site testing difference is difficult to resolve. The issue has been addressed over time with physical wind tunnel modifications, but this type of resolution is usually focused on getting correlation for a specific system or component of the vehicle, not addressing the entire vehicle.

A continuous demand for added multimedia features in the automotive audio systems not only requires adequate cooling of the internal electronics, but also the media itself. Thermal engineers focus their efforts only on keeping the electronics below thresholds by conventional methods such as internal fans, heat sinks, etc., while overlooking the CD media. The environment within the instrument panel (IP) poses additional challenge in maintaining the media at a temperature level that is comfortable to the human touch. Fans that would be a natural choice in such situations, could cause noise audible to the customer and thus create a new problem. A solid-state cooling device that uses Thermoelectric coolers (TEC) is proposed to keep the CD temperature low. The system comprises of TECs assembled with the hot side attached to a heat sink and the cold side attached to the radio top surface.

This paper evaluates the interaction between three design variables of a conventional extruded heat sink used for automotive audio systems in a passive convection environment. A 3-level Design of Experimentation (DOE) methodology, with a center point design, is utilized to quantify the non-linear behavior and the interaction effects between three design variables of the heat sink. A full factorial analysis of 27 CAE runs is employed to begin the DOE analysis. A second order non-linear response function is developed, using an estimated regression coefficient, that's used to optimize the heat sink design. The second-order quadratic model that includes the 2-way linear interactions between design variables is proven to be the model of choice that can characterizes the heat sink temperature more effectively and accurately.

Although automotive audio systems are getting increasingly sophisticated, cooling strategies are still primarily heat sink based. This paper describes the integration of a heat pipe into automotive radios in order to manage the heat in an effective manner. The heat pipe system proposed in this paper enables the heat produced by the devices to move and dissipate at a location outside of radio casing. The effectiveness of the system is validated experimentally by operating the radio with and without the heat pipe in a controlled environment and comparing the CD/media temperature in each case. It was found that heat pipe can be very effective not only in reducing the heat sink temperature, but also the media temperature.

The design and composition of heat shields is becoming a major factor in the design of future automobiles. The optimization of heat insulation materials is crucial in keeping size, mass, and cost to a minimum. The purpose of this paper is to describe the testing of four different fibrous insulating materials simulating 150,000 miles of the Underbody heat shielding that a light duty truck may experience. The materials were tested before and after the thermal durability experiment to show the degraded conduction performance of each sample.