Implementation of Unsteady Double-Axis of Rotation Motion to Predict Pitch-Damping Moment
Abstract
An investigation was performed to verify the implementation of double-axis rotation of a well-studied projectile (Army-Navy Finner) using an existing commercial fluid-flow solver by computing the pitch-damping moment (PDM) in multiple manners and comparing to previously published results. The PDM stability derivative was computed using 3 methods: 1) planar pitching, 2) lunar coning (steady and transient), and 3) equal and opposite coning-spinning motion. The investigation studied the effect of time step for the transient double-axis rotation simulation. Overall, the predicted body moments agreed quite well with results, suggesting that convergence can be achieved with further reduced global time step size. Although the unsteady double-axis rotation implementation study proved to be successful (i.e., verifying that the method can be used in transient simulations of projectiles undergoing complex kinematic motions), it is inefficient, and, therefore, may not be an advisable method to accurately predict PDM.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 18, 2016
- Accession Number
- AD1020435
Entities
People
- Joseph D. Vasile
Organizations
- United States Army Research Laboratory