Accession Number:

ADA263299

Title:

A Computational Study of the Base Region Flow Field for the M865 Projectile

Descriptive Note:

Final rept. Nov 1990-Jun 1991

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s):

Report Date:

1993-04-01

Pagination or Media Count:

37.0

Abstract:

Recent firing tests for the M865 projectile have indicated that for reasons unknown, the tracer in the base cavity region does not remain visible during the entire flight. To assist in analyzing this problem, a computational study has begun to examine the base region flow field for this projectile including the base cavity. Flow computations for this projectile have been performed at various supersonic Mach numbers, 2 M 5 and alpha 0.0 degree using a time marching Navier-Stokes code. The computed results show sharp changes in the centerline pressure distributions in the base region near M 3. This unexpected behavior may not be desirable and could be part of the problem. To minimize these pressure oscillations, several proposed configuration changes have been made in the afterbody base cavity region and computations have been performed for these modified configurations to analyze the effects on the flow field. One of these configuration with a new base cavity shape was found to improve the base region flow field. A modified version of this new base cavity has been flight tested and the results revealed some improvement in the visibility of the tracer compared to the original configuration.

Subject Categories:

  • Ammunition and Explosives
  • Ballistics
  • Operations Research
  • Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE