Global study of the mantle transition zone structure from geoid anomalies and SS w...
| Full text | |
| Author(s): |
Czelusniak, Luiz Eduardo
;
Cabezas-Gomez, Luben
;
Wagner, Alexander J. J.
Total Authors: 3
|
| Document type: | Journal article |
| Source: | Physics of Fluids; v. 35, n. 4, p. 14-pg., 2023-04-01. |
| Abstract | |
Direct simulations of phase-change and phase-ordering phenomena are becoming more common. Recently, qualitative simulations of boiling phenomena have been undertaken by a large number of research groups. One seldom discussed limitation is that large values of gravitational forcing are required to simulate the detachment and rise of bubbles formed at the bottom surface. The forces are typically so large that neglecting the effects of varying pressure in the system becomes questionable. In this paper, we examine the effect of large pressure variations induced by gravity using pseudopotential lattice Boltzmann simulations. These pressure variations lead to height dependent conditions for phase coexistence and nucleation of either gas or liquid domains. Because these effects have not previously been studied in the context of these simulation methods, we focus here on the phase stability in a one-dimensional system, rather than the additional complexity of bubble or droplet dynamics. Even in this simple case, we find that the different forms of gravitational forces employed in the literature lead to qualitatively different phenomena, leading to the conclusion that the effects of gravity induced pressure variations on phase-change phenomena should be very carefully considered when trying to advance boiling and cavitation as well as liquefaction simulations to become quantitative tools. (AU) | |
| FAPESP's process: | 16/09509-1 - Phase change heat transfer processes of high performance applied to solar energy recovery |
| Grantee: | Gherhardt Ribatski |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 18/09041-5 - Study of Lattice Boltzmann Method for modeling flows in microchannels of solar absorbers |
| Grantee: | Luiz Eduardo Czelusniak |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |