Surfactant effects on droplet formation in micro fluidic channels – MD modelling

Program Code: 

Dr Jong-Leng Liow (

Description of Work: 


Droplet formation in micro fluidic channels and micro-devices has significant applications in chemical and biological processing as well as in biomedical engineering. The diameter of the droplet formed is critically dependent on the physical properties of the dispersed phase and the dynamics of fluid flow. Surface or interfacial tension of the liquid-air, liquid-liquid and solid-liquid interfaces of the dispersed phase is one of the most important properties affecting the droplet formation mechanism. Other properties such as the viscosity of the dispersed phase and the concentration of the surfactants can also affect the droplet formation and the droplet diameter. This project will:

  • investigate the effects of the polysaccharide concentration in the dispersed phase on the viscosity of the solution using Molecular Dynamics (MD) simulations
  • investigate the interfacial forces between the surfactant and the water/polysaccharide mixture at the critical concentrations and determining liquid-liquid interfacial tension using MD simulations;
  • develop a hybrid MD and micro-fluid mechanics code to simulate the droplet formation process.

Description of Work:

  • Familiarisation with the NAMD MD code.
  • Build a model of a polysaccharide molecule(s) and carry out modelling of the motion of the molecule within a micro-channel to investigate slip effects and non-Newtonian flow behaviour.
  • Relate the results to the behaviour of the polysaccharide molecule(s) to experimental results on the drop formation in micro-channels.
  • There may be a possibility at the later stages of the project to spend time with collaborators in USA on this molecular dynamics project.


The prospective student(s) is expected to have some familiarity with experience in computer programming and use of computational packages and an understanding of chemistry.