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Fontenot, L. L.

Publications and source records attributed to Fontenot, L. L..

Slosh dynamics of a spin-stabilized spacecraft comprising off-axis tanks filled partially with liquid propellant

The fundamental nonlinear equations of motion were derived and the specialized to a steady-state rotation of the vehicle about a given axis of rotation. A thrust about the spin axis was introduced. A perturbation solution was derived which linearizes the problem. The effect of the centrifugal and coriolis accelerations together with vorticity are implicitly taken into consideration in the formulation. A variational formulation of the associated boundary conditions is presented. For practical cases it is shown that the simple classical pendulum representation for slosh is not very appealing for a spinning spacecraft unless severe restrictions are allowed.

Fontenot, L. L.↗

Analysis of cavitation bubble dynamics in a liquid

General differential equations governing the dynamics of the cavitation bubbles in a liquid were derived. With the assumption of spherical symmetry the governing equations were simplified. Closed form solutions were obtained for simple cases, and numerical solutions were calculated for complicated ones. The growth and the collapse of the bubble were analyzed, oscillations of the bubbles were studied, and the stability of the cavitation bubbles were investigated. The results show that the cavitation bubbles are unstable, and the oscillation is not sinusoidal.

Fontenot, L. L.↗

Stability of nonlinear vehicle systems

Nonlinear effects of liquid motion in fixed and moving containers on stability and control of liquid rocket powered missiles and spacecraft

LIQUID PROPELLANT↗