Algebraic Approximations to Extinction from Randomly Oriented Circular and Elliptical Cylinders

Abstract

Analytic approximations to the extinction efficiency, Q(ext), for oriented and randomly oriented circular infinite cylinders based on anomalous diffraction is given. The results are compared with the exact code. These results are further generalized to randomly oriented elliptical cylinders. Using the fomulae, Q(ext) can be evaluated over 10(exp 4) times faster than with the exact code. This approximation is valid for complex refractive indices m = n - ik, where 1 smaller or equal to n smaller or equal to infinity and 0 smaller or equal to k smaller or equal to 3, aspect ratios from 1 to 4 and modest to large particle sizes. The accuracy and limitations of this formula are discussed.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1995
Accession Number
ADA637615

Entities

People

  • B. T. Evans
  • G. R. Fournier

Organizations

  • DRDC Valcartier

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Abstracts
  • Aspect Ratio
  • Carbon Fibers
  • Classification
  • Computational Science
  • Computations
  • Diffraction
  • Equations
  • Fire Control Systems
  • Geometry
  • Integrals
  • Millimeter Waves
  • National Security
  • Particle Size
  • Refractive Index
  • Scattering
  • Standards

Readers

  • Analytical Mechanics
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering