3-D ALEGRA Simulations of Magnetic Field Shielding Effects of Conductive Tubes and Cups

Abstract

Full 3-D ALEGRA simulations were used to understand the shielding effects of copper tubes in direct comparison to copper cups with the magnetic field applied along the axis of the shapes and at 30 deg from the axis. Copper tubes with a diameter of 50 mm, a length of 80 mm, and wall thickness of 1 mm were investigated to determine the time the tube shielded an axial 0.25 T field applied as a step function. A variety of locations within the tube and near the tube were analyzed. The field was then applied at an angle of 30 deg from the axis to investigate shielding effectiveness. One end of the tube was then capped, making a cup shape, and identical simulations were repeated. While this produced nontrivial changes at the edges, the shielding effectiveness at the center of the shape was not significantly affected by either the applied field angle (up to the 30 deg investigated) or the capping of one end of the tube. Shielding effects and focusing of the field due to induced currents in the copper can create a considerable impact on field sensors and the detection of moving conductive particles.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 2018
Accession Number
AD1057898

Entities

People

  • W. C. Uhlig

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Air Platforms
  • Sensors
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundaries
  • Detection
  • Detectors
  • Diameters
  • Eddy Currents
  • Electrical Conductivity
  • Hypervelocity Projectiles
  • Images
  • Magnetic Fields
  • Military Research
  • Particles
  • Shape
  • Shielding
  • Simulations
  • Step Functions
  • Thickness
  • Three Dimensional

Readers

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