Accession Number:

ADA055282

Title:

Analysis of Water Drop Erosion Mechanisms in Infrared-Transparent Materials Using Microphysical Fracture Models.

Descriptive Note:

Final rept., Jun 76-Jul 77,

Corporate Author:

CALIFORNIA RESEARCH AND TECHNOLOGY INC WOODLAND HILLS

Report Date:

1977-10-01

Pagination or Media Count:

118.0

Abstract:

A theoretical program based on numerical simulations was conducted to investigate the response of infrared-transparent window materials zinc selenide and zinc sulfide to subsonic impacts 730 and 1120 fps of water drops 1 and 2 mm diameter. The approach is based on an analytical loading model of water drop impact and subsequent numerical code solutions of window response using a micro-mechanical crack propagation model. An analytical model has been developed to prescribe the pressure loading on the front surface of brittle targets during subsonic water drop impact. This model is a theoretical fit to numerical code results in a form which is consistent with physical assumptions concerning water drop impact. Due to the spherical geometry of the drop, an off-axis peak pressure occurs at early times which is greater than the 1-D Hugoniot value by about a factor of two.

Subject Categories:

  • Infrared Detection and Detectors
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE