NavierStokes computations for kinetic energy projectiles in steady coning motion: A predictive capability for pitch damping
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 has been applied to produce the first known NavierStokes predictions of the pitch damping for finned projectiles. The flow field about pinned kinetic energy projectiles in steady coning motion has been successfully computed using a parabolized NavierStokes computational approach. The computations make use of a rotating coordinate frame in order to solve the steady flows equations. From the computed flow field, the side moment due to coning motion is used to determine the pitchdamping coefficient. The computational predictions of the slope of the side moment coefficient with coning rate normalized by the sine of the angle of attack have been compared with pitch damping coefficients determined from range firings for two finned projectile configurations. The predictions show good agreement with the range data. This computational approach provides a significant predictive capability for the design of kinetic energy projectiles whose terminal ballistic performance can be degraded by moderate levels of yaw at the target.
 Publication:

Final Report
 Pub Date:
 April 1993
 Bibcode:
 1993arl..reptR....W
 Keywords:

 Bodies Of Revolution;
 Conical Bodies;
 Damping;
 Finned Bodies;
 Kinetic Energy;
 NavierStokes Equation;
 Prediction Analysis Techniques;
 Projectiles;
 Revolving;
 Aerodynamic Characteristics;
 Angle Of Attack;
 Flow Distribution;
 Numerical Analysis;
 Terminal Ballistics;
 Yaw;
 Fluid Mechanics and Heat Transfer