Pulsed Magnets—Advances in Coil Design Using Finite Element Analysis

We discuss further developments in the application of Finite Element Analysis (FEA) to the design of pulsed magnets on the basis of our latest coil design. Two areas are addressed. Firstly, we present results concerning the current distribution in the conductor during the discharge. Eddy current heating leads to thermal gradients across the layers and in the conductor; the results are compared with well established analytical codes. Significantly higher stresses result due to temperature gradients and nonuniform current distribution, which can be partly offset by pre-stressing reinforcement fibers. Secondly, we report progress in designs that facilitate much more rapid cool-downs for pulsed magnets, which can sometimes take in the order of hours between pulses. We show that cool-down times of 20 minutes or less are achievable using copper discs (designed using FEA) that will not support eddy currents