Angular Motion of a Spinning Projectile with a Viscous Liquid Payload
Abstract
Liquid payload motion can have a significant effect on the stability of a spinning projectile. A general definition of the liquid moment is developed and expressions are obtained for the frequencies and damping rates of the projectile's angular motion. An expression for the liquid pressure moment is derived without the unnecessary mathematical approximations of the Stewartson- Wedemeyer theory, and wall shear effects are added to this improved SW pressure moment to obtain the total liquid moment. This moment expression applies to cavities that are fully filled, partially filled or fully filled with a central rod. The improved theory shows that as the Reynolds number decreases, (a) the eigenfrequency-related side moment peaks decrease steadily in size but that (b) the average side moment level first increases and then decreases. This latter predicted behavior is in good qualitative agreement with the D'Amico-Miller conjecture that relates the liquid spin-down moment to the liquid side moment. Good agreement is also obtained between the theory and all available published data from liquid- filled gyroscope experiments.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1982
- Accession Number
- ADA118676
Entities
People
- Charles H. Murphy
Organizations
- Ballistic Research Laboratory