Abaqus Multiphysics / Thermal-Electric / Thermal-Electric Example

Thermal-Electric Modeling of an Automotive Fuse

Challenge

Fuses are the primary circuit protection devices in automobiles. They are available in a range of different current ratings and are designed so that when the operating current exceeds the design current for a period of time, heating due to electrical conduction causes the metal conductor to melt, thus the circuit to disconnect. Since the electrical conductivity of the fuse depends on temperature which in turn depends on the heat generated due to current flow, it is necessary to consider fully coupled thermal-electrical effects in the dsign of the fuse.

Solution

Temperature-dependent electrical and thermal conductivity, and the Joule heat fraction (representing the fraction of electrical energy dissipated as heat) are specified. Appropriate boundary conditions are imposed and a fully coupled thermal-electrical transient analysis under constant electrical current flow of 30 A is conducted and allowed to reach steady state conditions.

Benefit

Both the transient distribution of the current and temperature and the final steady state conditions determine the feasible range of operating conditions for the fuse. The thermal results may also be used to drive a subsequent structural analysis of the fuse so that thermal strains and phase changes can be studied.

Contours of electrical curent density in the fuse.

Contours of electrically-induced temperatures in the fuse.