Film flow over topography, when the topography is not completely wet by the film, while the fluids are either Newtonian or viscoelastic will be studied. Steady and dynamic simulations will use continuum models and numerical methods of solution such as FE or Cahn-Hilliard. Need to explore transitions between wetting and non-wetting states, hysteresis phenomena, etc.
Description
Film flows occur over a wide range of length and time scales and are central to numerous applications in engineering, physics & biomechanics. Flows over variable topography often lead to undesirable variations of film thickness or technologically important pattern formation. Often the flowing material is a polymer solution, but such studies are limited. In microelectronic applications, polymer solutions are used for coating substrates with micro-topography. Hence the developing film may not wet the trench or retain a uniform concentration, effects which dramatically decrease the product quality, but are not understood. In microfluidics, it is of interest to reduce drag by fabricating walls with periodic trenches of a few tenths of μm in dimension, inside which air is entrapped, and liquid cannot penetrate - super-hydrophobic surfaces. Trench geometry, flow direction, liquid-solid affinity, etc. play a crucial role in the development and maintenance of gas inclusions. This project aims at understanding the following: 1. Transient coating of patterned substrates allowing for air encapsulation in two and three dimensions 2. Stability of Newtonian or viscoelastic film flowing over patterned substrates with or without air inclusions between them 3. Stress-induced migration of polymer chains in solution in steady film flow over topography Skills and experience that will be considered positively include: 1. Knowledge of Fluid Mechanics and Rheology. 2. Programming in C#, C , FORTRAN and code parallelization. 3. Ability to work independently and as a team member. The selected researcher will receive financial support commensurate with his/her experience and skills, but will be no less than 2300 Euro. The deadline to accept applications has been extended to Sep. 15, 2014! All interested for the position should submit the following: 1. Detailed CV 2. Copies of previous degrees 3. Copies of scientific publications in Journals or presentations in Conferences, etc. 4. Names of 3 people that could provide reference letters 5. Their skype address for direct communication and possible interview.
Benefits
Full time occupation and full time salary of min 2300 Euro / month
