Transient Modeling Techniques for the Analysis of Electromagnetic Launchers

2021-9-7
Tosun, Nail
Although electromagnetic launchers (EMLs) are better than gun-powder-based launchers, they have to endure severe electrical and mechanical conditions. Therefore, the optimal design and accurate simulations of these devices are essential. The inductance and electromotive force (EMF) variations in the transient, which significantly impact the launch process, are modeled. Moreover, velocity skin effect (VSE) is added to the EML calculations in an effective way. Commercial finite element software cannot solve the electromagnetic aspects of such a high-speed application with a transient solver in 3-D. Although 2-D approximations can be used, such an approximation overestimates VSE resistance due to geometry simplifications. In this thesis, a novel quasi-transient 3-D Finite Element Method (FEM) model where the air-armature region's conductivity is varied to emulate the high-speed motion of the armature is proposed. These propositions are compared for experimental results with different EMLs, EMFY-1, and EMFY-2 and showed good agreement.

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Citation Formats
N. Tosun, “Transient Modeling Techniques for the Analysis of Electromagnetic Launchers,” M.S. - Master of Science, Middle East Technical University, 2021.