Grivet Rodolphe, Monier Antoine, Huerre Axel, Josserand Christophe, Séon Thomas
Laboratoire d'Hydrodynamique (LadHyX), UMR 7646 CNRS-Ecole Polytechnique, IP Paris, 91128 Palaiseau, France.
Institut Jean Le Rond ∂'Alembert, UMR 7190, CNRS-Sorbonne Université, F-75005 Paris, France.
Phys Rev Lett. 2022 Jun 24;128(25):254501. doi: 10.1103/PhysRevLett.128.254501.
The effect of freezing on contact line motion is a scientific challenge in the understanding of the solidification of capillary flows. In this Letter, we experimentally investigate the spreading and freezing of a water droplet on a cold substrate. We demonstrate that solidification stops the spreading because the ice crystals catch up with the advancing contact line. Indeed, we observe the formation and growth of ice crystals along the substrate during the drop spreading, and show that their velocity equals the contact line velocity when the drop stops. Modeling the growth of the crystals, we predict the shape of the crystal front and show that the substrate thermal properties play a major role on the frozen drop radius.
冷冻对接触线运动的影响是理解毛细管流凝固过程中的一个科学挑战。在本快报中，我们通过实验研究了水滴在冷基底上的铺展和冻结情况。我们证明，凝固会阻止铺展，因为冰晶赶上了前进的接触线。实际上，我们观察到在液滴铺展过程中沿基底形成并生长的冰晶，并表明当液滴停止时，它们的速度等于接触线速度。通过对晶体生长进行建模，我们预测了晶体前沿的形状，并表明基底的热性能对冻结液滴的半径起着主要作用。
