Yaw instabilities produced by rapidly rotating, highly viscous liquids
Abstract
A liquidfilled gyroscope was used to study the yaw instabilities for low Reynolds numbers. Control of physical variables produced a range in Reynolds number (Re) of 5 to 12 x 10 to the 3rd. The gyroscope is freely gimballed and spun at a constant rate by a dc motor. The logarithmic amplitude of the gyroscope motion grew linearly with time, and linear behavior was observed for precession angles smaller than 5 deg. The data suggested that the growth rates also varied linearly with the coning frequency, tau(R), of the liquidsolid parts. The strongest correlation for the amplitude growth rate of high viscosity liquids occurred for the product Re x tau(R). The experimental demonstration of growth rates proportional to the coning frequency is not consistent with the classical liquidinduced instability, which is based upon a resonant matching of a natural frequency of oscillation of the fluid and the coning frequency.
 Publication:

AIAA, Aerospace Sciences Meeting
 Pub Date:
 January 1981
 Bibcode:
 1981aiaa.meetU....D
 Keywords:

 Gyroscopic Stability;
 Liquid Filled Shells;
 Rotating Liquids;
 Viscous Fluids;
 Yaw;
 Flight Stability Tests;
 Reynolds Number;
 Instrumentation and Photography