Viscous fluid buckling: A theoretical and experimental analysis with extensions to general fluid stability
Abstract
The spontaneous oscillations observed when a very viscous fluid flows from an orifice vertically against a flat surface were studied using silicone oils of very high viscosities as the main working fluids. The "moving threadline" equation is shown to also govern the oscillations of the fluid column and it is suggested that certain conclusions reached in the study of the "moving threadline" have direct application to the problem of fluid buckling. Results are presented in nondimensional form for the buckling height, the plate orifice distance at which the spontaneous oscillations first occur and the behavior of these oscillations as functions of geometrical fluid and flow properties for both axisymmetric and plate jets. Analytical solutions for the "viscous gravity" jet profile are compared with the experimentally determined jet profile and with the numerically obtained solutions of the complete one dimensional equations (including inertia and surface tension). The existence of a "jump" or discontinuity in the oscillations of the jet is postulated.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1980
- Bibcode:
- 1980PhDT........82C
- Keywords:
-
- Dynamic Response;
- Flow Distortion;
- Flow Stability;
- Oscillating Flow;
- Viscous Fluids;
- Buckling;
- Flow Geometry;
- Flow Visualization;
- Jet Flow;
- Silicones;
- Viscous Flow;
- Fluid Mechanics and Heat Transfer