"220V AC Cooling Fan" electric analog simulation method and its application will help put some abstract objects become more intuitive, so-called electric conductive circuit simulation is to simulate the electronics cooling loop. Electrical parameters to model heat transfer. Specifically, the current in the circuit that is used to simulate the thermal circuit of the heat Q (in the calculation, the semiconductor device power dissipation PD commonly used in place of the heat Q), "220V AC Cooling Fan" is represented by the flow of current heat delivery. Voltage V is equivalent to the temperature difference △ T, the equivalent thermal resistance R Rth. To radiation is concerned, because this is a non-linear heat transfer model, and therefore can not derive formulas similar to thermal conduction and convection to. Thermal resistance is a very useful concept. "220V AC Cooling Fan" heat sink thermal resistance is usually used to represent its properties. Thermal parameters of power semiconductor devices is based on the junction-to-case thermal resistance to labels.