Aiming at the low accuracy of element melt method in predicting the wave melt ablation(WMA)velocity
a new finite element method of melt wave ablation is proposed. Based on a two-dimensional governing equation of electromagnetic rail launcher
a Galerkin-form finite element discrete formulation for dealing with moving boundary by potential moving methodis derived
then the finite element model of transient electromagnetic-thermal-moving coupling problem in two dimensions is established. Using node element as the criterion
the armature WMA model is built. Computational results show that when the armature moving speed is 150 m/s and the applied magnetic induction intensity is 40 T
the WMA velocity predicted by the node melt method(NMM)is 94% of that predicted by Barber's models
while the WMA velocity predicted by Stefani using element melt method(EMM)is 73% of that predicted by Barber's models. Thus
compared with EMM
the WMA velocity predicted by NMM is closer to the results of Parks' and Barber's classic models
which verifies the correctness of the proposed NMM method.
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references
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