Geometry Design and Contact Force Analysis of C-shaped Monolithic Armature

doi:10.3969/j.issn.1000-1093.2019.10.001

Abstract

Abstract:

The proper electrical contact performance in the initial section of rail is the necessary condition to ensure the normal firing of railgun. In order to enhance the electrical contact performance, an optimal design of C-shaped monolithic armature structure is proposed from two aspects of contact surface and contact pressure. The influence of contact surface on the electromagnetic characteristics of armature is analyzed to obtain the current density and electromagnetic force curves by using high frequency eddy current simulation method. The optimum size and position of contact surface are obtained through comparison and analysis. In order to avoid the contact failure during initial motion, the traditional contact pressure design method (“1 g/1 A”) was modified and optimized to form a transient application method of “1 g/1 A”. The proposed method can be used to simulate the transient characteristics of contact pressure effectively. The proposed method is applied to calculate the contact forces on the different contact surfaces during the initial stage of launching. The calculated results show that the contact force curves of armature and rail are all above the equivalent“1 g/1 A” force curve, which proves that the method can ensure a proper contact between armature and rail. The armature designed by using the transient application method of “1 g/1 A” was tested under the optimal contact surface, in which the better electrical contact in the initial section of rail was achived. Key

Key words: electromagneticrailgun, C-shapedmonolithicarmature, contactsurfacebetweenarmatureandrail, armaturestructure, contactforce, numericalcalculation, electromagneticlaunchexperiment

CLC Number:

TJ866

FAN Wei， SU Zizhou， FAN Tianfeng, ZHANG Tao， ZHANG Honghai， LIU Yong. Geometry Design and Contact Force Analysis of C-shaped Monolithic Armature[J]. Acta Armamentarii, 2019, 40(10): 1969-1976.

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第40卷
第10期2019 年10月兵工学报ACTA
ARMAMENTARIIVol.40No.10Oct.2019

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