Calculative Method on Electromechanical Strength for Rectangular and T-Shaped Rail over a Flat Surface Armature
DOI:
https://doi.org/10.13052/2024.ACES.J.390908Keywords:
Area’s moment of inertia, armature velocity, critical velocity, dynamic analysis, electromagnetic railgun launching, electromechanical strength, Maxwell-Simplorer coupledAbstract
The electromagnetic railgun launching (EMRL) system is a type of long-range projectile launch that does not require any chemical propellant and can accelerate masses ranging from milligrams to kilograms to velocities of more than several kilometers per second. To make the rail stronger, electromechanical strength analysis was performed by calculating the area’s moment of inertia and critical velocity. One of the most essential mechanical aspects of rails is their moment of inertia, which has a direct impact on critical velocity and launch performance. Geometry and material both have an impact on the rails’ electromechanical performance. This paper describes the increase in electromechanical performance achieved by constructing two types of rail cross-sections - rectangular rails and T-shaped rails - based on structural analysis and current distribution from coupled electromagnetic (EM) simulation. The investigation found that T-shaped rails have higher moments of inertia than rectangular rails for the same cross-sectional area and width. However, the mechanical performance differences between the two geometries are not significant. Therefore, the advantage of larger moments of inertia for a given cross-sectional area is limited. EM analysis has been extended to a 3-D finite element method (FEM) for both rails by linking it with Simplorer using the Maxwell-Simplorer coupled (MSC) method with a flat surface C-shaped armature. When compared to rectangular and T-shaped rails, the T-shaped rail has a lower current density at the inner curvature but a greater at the contact interface.
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