Gibbons M J, Garivalis A I, O'Shaughnessy S M, Robinson A J, Di Marco P
Department of Mechanical, Manufacturing & Biomedical Engineering, Trinity College Dublin, the University of Dublin, Dublin 2, Ireland.
DESTEC, University of Pisa, Largo Lazzarino 1, Pisa, 56122, Italy.
NPJ Microgravity. 2024 May 7;10(1):52. doi: 10.1038/s41526-024-00396-2.
Sessile water droplet evaporation in varied gravity and electric fields has been experimentally studied. Specifically, the influences of gravity and electric fields are investigated in the context of the heat flux distribution beneath the droplets, as well as the droplet mechanics and resulting shapes. Experimental testing was carried out during a European Space Agency (ESA) Parabolic Flight Campaign (PFC 66). The droplets tested evaporated with a pinned contact line, a single wettability condition, and varied droplet volume and substrate heat flux. The peak heat transfer was located at the contact line for all cases. The peak heat flux, average heat flux, and droplet evaporation rate were shown to vary strongly with gravity, with higher values noted for hypergravity conditions and lower values in microgravity conditions. The droplet thermal inertia was shown to play a significant role, with larger droplets taking more time to reach thermal equilibrium during the parabolic testing period. No significant impact of the electric field on the droplet evaporation was noted for these test conditions.
已对不同重力和电场条件下的静态水滴蒸发进行了实验研究。具体而言，研究了重力和电场对液滴下方热通量分布、液滴力学及最终形状的影响。实验测试是在欧洲航天局（ESA）的抛物线飞行任务（PFC 66）期间进行的。所测试的液滴在固定接触线、单一润湿性条件下蒸发，且液滴体积和基底热通量各不相同。在所有情况下，峰值热传递均位于接触线处。结果表明，峰值热通量、平均热通量和液滴蒸发速率随重力变化显著，超重力条件下的值较高，微重力条件下的值较低。液滴热惯性起着重要作用，在抛物线测试期间，较大的液滴达到热平衡所需的时间更长。在这些测试条件下，未发现电场对液滴蒸发有显著影响。
