ESR 3: Solidification of a supercooled water drop after an impact onto anti-icing substrates

Technische Universit├Ąt Darmastadt, Darmstadt (Germany)

Researcher: Mingyue Ding

Supervisor: Ilia Roisman

Project goals:

The rate of heterogeneous nucleation on complex solid substrates is influenced by specific coating chemical properties, surface morphology and by drop impact. It determines the conditions for the inception of the freezing. A universal model for heterogeneous ice nucleation is still missing.

The objectives of the project include better understanding the physics of the ice heterogeneous nucleation in a spreading or propagating supercooled drop on complex substrates. Two main processes will be studied: i) single drop impact onto a cold substrate and ii) drop propagation on a substrate under the action of an air flow.

The ESR will be responsible for the experimental project which objectives include the measurement of the nucleation rates and probabilities of supercooled (up to -20 ┬░C) drop solidification on complex substrates due to heterogeneous nucleation after high-speed drop impact and shear-driven drop propagation in the TUDA wind channel. The phenomena are governed by the fast growth of the mushy layer of dendrites, viscous and thermal boundary layers, bubble entrainment. Various designs of anti-icing substrates will be used in experiments, including the substrates produced by the partners in the SURFICE consortium. ESR3 will be also hosted by Prof. A.L. Yarin at UIC (USA) and by ANSYS (Canada) supporting the computations and development of a theoretical model for nucleation and freezing of an impacting drop.