Prof. Martin Horsch's Talk

Jan 25, 2017 - 16:00

Jan 25, 2017 - 17:00

Rm. No. 240 Chemical Engg. Dept.

Seminars

Prof. Martin Horsch University of Kaiserslautern Germany and IIT Kanpur

Abstract: At the transition to the nanoscale interfacial and finite-size effects become significant which are often neglected in phenomenological models. The properties and the dynamics of dispersed phases contact lines and nanostructured systems are hard to capture experimentally due to the high resolution which is required and the short time scale on which phase transitions and fluctuations may occur. Therefore in the present work massively-parallel molecular dynamics simulation with the scalable code ls1 mardyn [1] is applied to wetting phenomena. For sessile droplets on a perfectly planar solid substrate the dependence of the contact angle on the magnitude of the dispersive fluid-substrate interaction and the temperature is characterized for Lennard-Jones model systems [2 3]. On this basis contact line pinning is discussed for heterogeneously patterned surfaces in the impregnation wetting regime and for the epitaxial Cassie state where a contact line of an advancing droplet is stuck at an edge. In this way the influence of the surface morphology on the contact angle and the contact line is captured with molecular resolution. The perspective for multiscale modelling and simulation approaches is discussed [4] and it is shown how molecular simulation results can complement experimental data on the surface morphology of alkylsilane self-assembled monolayers on a silica substrate [5]. [1] C. Niethammer S. Becker M. Bernreuther M. Buchholz W. Eckhardt A. Heinecke S. Werth H.-J. Bungartz C. W. Glass H. Hasse J. Vrabec M. Horsch ls1 mardyn: The massively parallel molecular dynamics code for large systems J. Chem. Theory Comput. 10(10) 4455-4464 2014. [2] M. Horsch M. Heitzig C. Dan J. Harting H. Hasse J. Vrabec Contact angle dependence on the fluid-wall dispersive energy Langmuir 26(13) 10913-10917 2010. [3] S. Becker H. M. Urbassek M. Horsch H. Hasse Contact angle of sessile drops in Lennard-Jones systems Langmuir 30(45) 13606-13614 2014. [4] F. Diewald C. Kuhn R. Blauwhoff M. Heier S. Becker S. Werth M. Horsch H. Hasse R. Müller Simulation of surface wetting by droplets using a phase field model Proc. Appl. Math. Mechan. 16 519-520 2016. [5] J. M. Castillo M. Klos K. Jacobs M. Horsch H. Hasse Characterization of alkylsilane self-assembled monolayers by molecular simulation Langmuir 31(9) 2630-2638 2015.Bio: Prof. Horsch did his PhD in Mechanical Engineering at the University of Stuttgart and the University of Paderborn (2006-2010). He did his postdoctoral work at the Imperial College London and joined as Junior Professor of Computational Molecular Engineering at the Department of Mechanical and Process Engineering in University of Kaiserslautern. He is also currently a Visiting Associate Professor at IIT Kanpur. Note: Attendance is mandatory for those enrolled in CL 704/702.