Accession Number:

ADA285866

Title:

Navier-Stokes Predictions of Pitch-Damping for Axisymmetric Shell Using Steady Coning Motion

Descriptive Note:

Final rept. Jan 1989-Jun 1993

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Report Date:

1994-09-01

Pagination or Media Count:

44.0

Abstract:

Previous theoretical investigations have proposed that the side force and moment acting on a body of revolution in steady coning motion could be related to the pitch-damping force and moment. In the current research effort, this approach is applied to produce predictions of the pitch-damping for axisymmetric shell. The flow fields about these projectiles undergoing steady coning motion are successfully computed using a parabolized Navier-Stokes computational approach which makes use of a rotating coordinate frame. The governing equations are modified to include the centrifugal and Coriolis force terms due to the rotating coordinate frame. From the computed flow field, the side moments due to coning motion, spinning motion, and combined spinning and coning motion are used to determine the pitch-damping coefficients. Computations are performed for two generic shell configurations a secant-ogive-cylinder and a secant-ogive-cylinder-boattail. Predictions are made for various length-to- diameter ratios and supersonic Mach numbers and comparisons made with results obtained using a previously published inviscid code. Results are also obtained for a series of ogive-cylinder configurations which have been tested in an aerodynamics range. The comparisons between computational predictions and the range data confirm the validity of the theoretical approach. Projectiles, Aerodynamic characteristics, Computational fluid dynamics, Pitch-damping.

Subject Categories:

  • Guided Missile Dynamics, Configurations and Control Surfaces
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE