Natural convection above circular disks of evaporating liquids

Benjamin Dollet (1) , François Boulogne (2)

1 IPR - Institut de Physique de Rennes
2 LPS - Laboratoire de Physique des Solides

We investigate theoretically and experimentally the evaporation of liquid disks in the presence of natural convection due to a density difference between the vapor and the surrounding gas. From the analogy between thermal convection above a heated disk and our system, we derive scaling laws to describe the evaporation rate. The local evaporation rate depends on the presence of a boundary layer in the gas phase such that the total evaporation rate is given by a combination of different scaling contributions, which reflect the structure of the boundary layer. We compare our theoretical predictions to experiments performed with water in an environment controlled in humidity, which validate our approach.

Domaines: Mécanique des fluides [physics.class-ph]

Benjamin Dollet, François Boulogne. Natural convection above circular disks of evaporating liquids. Physical Review Fluids, 2017, 2 (5), pp.053501. ⟨10.1103/PhysRevFluids.2.053501⟩. ⟨hal-01525070⟩