Optimization of the coupled cooling circuit in electromagnetic forming with finite element analysis

Abstract

Electromagnetic forming has good prospects in light alloy forming. In the EMF process, intense current causes considerable temperature rise in the driving coil, which may reduce the service life of the driving coil. The cooling circuit method is one of the ways to solve this problem by using mutual inductance between the driving coil and the cooling coil to transfer Joule heat. This paper derives the dependence of cooling efficiency on circuit parameters. Then with a validated finite element model, the influence of coupling coefficient, discharge frequency, coil turns, and impedance angle on EMF process are analyzed in detail. The simulation results are in good agreement with the theoretical prediction. In addition, the influence of the switch-on time on the cooling effect and deformation is analyzed at two different frequencies. With the optimized parameter and switch-on time, the Joule heat in the driving coil during the EMF process has a considerable decrease especially at a higher frequency.