Stability in spherical systems. 1: hydrodynamic stability of thin, spherically concentric fluid shells. 2: Global stability of transient drop extraction
Abstract
Two studies of hydrodynamic stability in spherical systems were conducted. The first considers the problem of thin film stability in spherically concentric fluid shells by means of the traditional linear hydrodynamic stability theory. Experimental observations confirmed that the critical thickness at rupture is independent of the hydrodynamic interfacial stress condition. However, film thicknesses at rupture were about five times greater than predicted due to nonspherical concentricity of the fluid phases in the experiment. The second study uses the nonlinear method of energy to examine the stability of transport in a drop characterized by an impulsive change in boundary temperature or concentration. Instabilities driven by interfacial n gradients are considered for two diffusive base states: the stagnant spherical drop model proposed by Newman and the circulating drop model of Kronig and Brink. Stability curves generated clearly show the presence of an onset time and a decay time for the disturbances. Comparison with limited available experimental data shows that qualitative prediction based upon the theory are observed experimentally.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- March 1980
- Bibcode:
- 1980PhDT........40P
- Keywords:
-
- Interfacial Tension;
- Prediction Analysis Techniques;
- Shell Stability;
- Spherical Shells;
- Thin Films;
- Film Thickness;
- Hydrodynamics;
- Interfaces;
- Investigation;
- Fluid Mechanics and Heat Transfer