Test The Limits

How to Keep Your Vehicle Brain Cool on a Hot Summer Day

By Kamalesh Bhambare

October 06 2016

Today’s infotainment system is the brain of a modern vehicle as it provides its operating information and the information on its surroundings. It helps the driver navigate and operate the vehicle safely. This critical system requires extra thermal management attention because of the cooling needs complex electronics have in hot climates.

 

This problem was studied in the SAE paper (SAE 2015-01-0328) with the infotainment system exposed to solar heat up and AC cooldown. Some consider this to be the worst case thermal scenario the infotainment system can get exposed to. This is usually tested by placing the vehicle into a climatic wind tunnel with an array of solar lamps and hot, still air surrounding it. These extreme conditions cause high temperatures in the cabin and heat up the infotainment system. Temperatures can be so high that without cooling the electronics will not be able to operate. To fix this, the air conditioner is used to cool the electronics in addition to the cabin.

 


Car in solar heat and AC is nearly ideal. 

 

Simulations were performed using coupled fluid-thermal solver approach. The simulations included fully detailed vehicle structure, materials in the cabin, and detailed geometry and infotainment electronics heat generation. The lamp array in the climatic wind tunnel was modeled in PowerTHERM. The unique transient solver in PowerFLOW properly captured the buoyancy effects on temperature distribution in the cabin. Good agreement between the results of the simulation process and experiment in a controlled climatic facility has been obtained. Particularly, the soak stage shows excellent trend capturing ability. This is especially important as the ability to predict fluid temperatures in regions considered to house infotainment units can influence decisions on packaging very early in a car's design phase. Cabin ambient temperature correlation is nearly ideal.

 

The developed simulation methodology yields a fast enough turnaround time for the use in vehicle programs. It provides early assessment of the environment impact on the vehicle climate control. It can reproduce the experimental conditions, or environmental conditions the vehicle can be exposed to. This will support better packaging of infotainment units and reducing the cooling requirements.

 

Infotainment instrument panel surface temperature (Top) and driver breath level air temperature (Bottom):



 

 

 

Reference:
Jansen, W., Amodeo, J., Wakelam, S., and Bhambare, K., "Automotive Cabin Infotainment System Thermal Management," SAE Technical Paper 2015-01-0328, 2015