Back to Search
Start Over
Turbulent thermal convection driven by free-surface evaporation in cuboidal domains of different aspect ratios
- Source :
- Physics of Fluids, Physics of Fluids, American Institute of Physics, 2021, 33 (1), pp.015104. ⟨10.1063/5.0035277⟩, Physics of Fluids, Vol. 33, no.1, p. 015104 (2021)
- Publication Year :
- 2021
- Publisher :
- HAL CCSD, 2021.
-
Abstract
- International audience; In this paper, we present simulations of turbulent thermal convection driven by free-surface evaporation above and by a heated wall below. A novel algorithm is proposed for predicting evaporation rates at a free surface, which we then validate against experimental data. At the top of a cuboidal domain, a shear-free boundary condition acts as an approximation of the free surface. We first focus on a domain of aspect ratio Γ = 1, where a fully resolved direct numerical simulation is carried out at a moderate Rayleigh number, Ra = 1.2 × 107, and we compare flow statistics with a Large-Eddy Simulation (LES) on a coarse grid. Both the fully resolved simulation and the LES predict well the time- and area-averaged evaporation rate and free surface temperature when compared with the experimental data. Next, we carry out a series of LES with an increasing lower wall temperature and, consequently, Ra. We then validate the evaporation model by comparing LES predictions of the time- and area-averaged mass flux and temperature at the upper boundary against the experimental measurements. The aspect ratio of the domain is then reduced, and we show, for the first time, the transition to a dual-roll state of the large-scale circulation (LSC) at the aspect ratio of Γ = 1/4 in a cuboidal domain. The temperature and velocity distributions at the free surface are impacted by the state of the LSC. However, we find that the water-side turbulence and aspect ratio play a negligible role on the evaporation rate above, in accordance with experimental observations.
- Subjects :
- Mass flux
Convective heat transfer
Computational Mechanics
Evaporation
Direct numerical simulation
natural convection
turbulent flows
01 natural sciences
Large Eddy Simulations
010305 fluids & plasmas
evaporation
Physics::Fluid Dynamics
[SPI]Engineering Sciences [physics]
0103 physical sciences
010306 general physics
Fluid Flow and Transfer Processes
Physics
Turbulence
Mechanical Engineering
Rayleigh number
Mechanics
Condensed Matter Physics
Aspect ratio (image)
turbulent convection
Mechanics of Materials
Free surface
Subjects
Details
- Language :
- English
- ISSN :
- 10706631 and 10897666
- Database :
- OpenAIRE
- Journal :
- Physics of Fluids, Physics of Fluids, American Institute of Physics, 2021, 33 (1), pp.015104. ⟨10.1063/5.0035277⟩, Physics of Fluids, Vol. 33, no.1, p. 015104 (2021)
- Accession number :
- edsair.doi.dedup.....1d64df746237c9c0b8c7f38e13329b5e