Use of the SIMBAD Gun Dynamics Code for Modelling the In-Bore Dynamics of EM Launchers

Abstract

Generic SIMBAD models of various Electro-Magnetic (EM) launchers have been used in the UK for studying model the in-bore phase and launch accuracy issues of such systems. Although many of features of the EM environment are not modelled with any degree of complexity, SIMBAD still provides a useful tool for investigating some of the dominant material and geometric influences on the in-bore dynamics and launch accuracy. Modifications to the SIMBAD code allowed for the simulation of asymmetrical electro-magnetic forces acting on the projectile. Other modifications allowed for the simulation of some of the time varying asymmetries in the forces on the projectile. These have demonstrated that there may be additional EM influences contributing to in-bore projectile balloting. Comparative performance data was produced for three shot designs (U4, U7 and U9 projectiles) simulated being fired from the 90 mm IAP and Task C launchers, and highlighted their typical in-bore performance characteristics. Transverse accelerations on the projectiles showed typical peak values of 6,000 g. higher values and degradation in projectile performance was demonstrated due to increasing wear and distortion in the launcher's core when experimental bore straightness and wear were included. Initial values for projectile exit conditions from the launchers were produced, which demonstrated increased sensitivity of shot jump, pitch and pitch rate in the vertical plane and some important differences between projectile designs.

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Document Details

Document Type
Technical Report
Publication Date
Apr 26, 2001
Accession Number
ADP012473

Entities

People

  • A. M. Dilkes437
  • D. W. Lodge

Tags

DTIC Thesaurus Topics

  • Armatures
  • Assembly
  • Bending Moments
  • Composite Materials
  • Displacement
  • Elements
  • Frequency
  • Frequency Response
  • Geometry
  • Guns
  • Materials
  • Modal Analysis
  • Projectile Components
  • Projectiles
  • Resonant Frequency
  • Shear Stresses
  • Simulations

Readers

  • Computational Modeling and Simulation
  • ballistics.