Workshop meeting Lorentz Center Contact Line Instabilities

Influence of surface tension gradients:

thermal gradient and surfactants

Hein Castelijns, Alexander ZdravkovASML

Slide 2 |

Participants

Hein Castelijns

Alexander Zdravkov

Chuangxin Zhao

Mariano Galvagno

Michael Köpf

Marco Baragona

Uwe Thiele

Laurent Limat

Slide 3 |

Subject 1:

Liquid metal (weld pool)

• Inward Marangoni flow air entrainment in weld

• Forward Marangoni flow instability (fingering)

Outcome: suggestions to literature and possibly numerical modelling

Chuangxin Zhao

Slide 4 |

Subject 2:

“Coffee stain” / pattern formation in drying droplets/films

How Marangoni effects come into play?

Outcome:

• References to recent papers, e.g. on coffee stain avoidance by Marangoni flow

• ASML has interest in drying stain formation

• Discussion about model applicability

Laurent Limat

Slide 5 |

Manipulation of droplet on (hydrophilic) surface

Questions:

• How to use to maximize droplet velocity?

• What is the effect of the precursor film on this phenomenon?

Subject 3:

Qvapor

movie

ASML

Droplet size ~ 3 mm, initi ~ 4°, end ~ 15°, velocity ~ 5 mm/s

Slide 6 |

Manipulation of droplet on (hydrophilic) surface

Outcome:

• discussion about phenomenon and modelling

• suggestion to look at surfactant systems (self-running droplets)

• other types of droplet manipulation (vibration etc.)

• surface structure slip?

• localizing in application

Subject 3: ASML