Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.
A methodology for modeling and simulating electro-thermal system in an enclosed electronic package is presented. The electro-thermal model was constructed by using system dynamics, particularly the bond graph methodology. The system model, in which the electrical domain and the thermal domain are coupled, is presented. The system model described its dynamic thermal behaviour of the system caused by heat generation from the electronic package which in located in the test enclosure chamber. The system model included the time-variant thermal parameters such as environment variation and with incoming heat flow variation. In detail, an effective way to identify the time-variant thermal parameters of the system with considering transient thermal behaviour using temperature difference between nodes was suggested. The system model contains the variation of heat flow derived by resistance change of resistive heater in electronic device increasing with temperature rise of heater, and the variation of ambient air temperature. The electro-thermal system model was validated when the system has time-variant thermal parameters such as variation of convection and contact resistance. The proposed system model shows good agreement with measured temperature response in the transient state corresponding to the variance of environment.