Transport Phenomena - Delft University of Technology

Michiel Musterd

Michiel Musterd

Non-Idealities in Multiphase Millifluidics Caused by Partial Wetting

Contact details

  • Ir. Michiel Musterd
  • Delft University of Technology, TNW-PPE/TP
  • Room 0.529
  • Julianalaan 136, The Netherlands

Research interests

  • Partial wetting microflows
  • Contact line statics and dynamics
  • CFD of surface tension dominated flows (OpenFOAM)
  • Multiphase flow in porous media
  • Equilibrium modelling of capillarity (Surface Evolver)

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Latest publications

  • Droplets on Inclined Plates: Local and Global Hysteresis of Pinned Capillary Surfaces, Michiel Musterd, Volkert van Steijn, Chris R. Kleijn, and Michiel T. Kreutzer. Physical Review Letters 2014, 113  (6), published on–line.
    [Full Details]     [BibTeX]     Publisher: [DOI] 
  • On the Fabrication of Pdms Micromodels by Rapid Prototyping, and Their Use in Two-Phase Flow Studies, N. K. Karadimitriou, M. Musterd, P. J. Kleingeld, M. T. Kreutzer, S. M. Hassanizadeh, and V. Joekar-Niasar. Water Resources Research 2013, 49  (4), 2056–2067.
    [Full Details]     [BibTeX]     Publisher: [DOI] 
  • Prediction of Droplet Deformation and Roll-off From an Inclined Plate, M. Musterd, V. van Steijn, C. R. Kleijn, and M.T. Kreutzer. In 1st Int. Workshop on Wetting and Evaporation:droplets of pure and complex fluids, 17-20 June 2013, Marseilles, 2013.
    [Full Details]     [BibTeX]     Publisher: (unavailable)
  • Improved Reproducibility of Droplet Pinning Measurements on Microscopically Heterogeneous Surfaces, M. Musterd, V. van Steijn, C. R. Kleijn, and M.T. Kreutzer. In Proceedings of the 3rd European Conference on Microfluidics, 3-5 Dec 2012, Heidelberg, 2012.
    [Full Details]     [BibTeX]     Publisher: (unavailable)
  • Volatile Tracer Dispersion in Multi-Phase Packed Beds, Nathalie Marquez, Michiel Musterd, Pedro Castano, Rob Berger, Jacob A. Moulijn, Michiel Makkee, and Michiel T. Kreutzer. Chemical Engineering Science 2010, 65  (13), 3972–3985.
    [Full Details]     [BibTeX]     Publisher: [DOI] 

Student projects


  • MSc with honors - Chemical Engineering, Delft University of Technology (2010)
  • BSc with honors - Chemical Engineering, Delft University of Technology (2008)



Research description


In contrast to conventional reactors, the fluid dynamics in multiphase micro- and millireactors are dominated by capillary forces. In partial wetting systems, where energy minimization is obtained with part of the walls in contact with the secondary phase, wall adhesion is an additional factor that can significantly influence the flow. In effect the microscale roughness of the reactor walls (see figure below) changes the flow dynamics and with that the reactor performance.

In this project we aim to develop a CFD model to predict multiphase flow in micro- and millifluidic channels under partial wetting conditions. The focus is on understanding and controlling the dynamics of the gas-liquid-solid interface for channels with and without internal structure.

Currently, we investigate the phenomenon of contact line pinning, in which a droplet is immobilized through chemical or physical obstacles (defects). Although the mechanism for this phenomenon is well understood, only models for limiting cases like single defects and thermodynamic averages are available.

Interested? If you are looking for a MSc or BSc project in this field, you can always drop by my office or send me an email at

Image of a two-phase flow in a rough walled channel

Current research topics

Pinning of droplets on heterogeneous surfaces

In our experiments we design micropillar arrays on which a water droplet will be suspended in the Cassie state. In this way the droplet 'feels' a physically homogeneous but chemically heterogeneous surface (patches of air and solid). By varying the spatial properties of the pillars we study how a 'real' surface would pin a droplet in place.

The experimental setup consists of a tilting table with a camera mounted on the axis. In this way our reference frame is the tilting table and therefore we can study the deformation of the pinned droplet without having to correct for a tilting baseline. An example of a pinned droplet which is slowly tilted is shown in the video below.

Interplay of channel obstructions and wettability in droplet breakup

The dominant capillary forces in micro- and millichannels can cause droplets to break up when flowing through an obstacle. We study this phenomenon numerically with the CFD package OpenFOAM and focus on the effect of the wettability of the walls which can both stabilize or destabilize the droplet when moving through the obstruction. The droplet moving through the cross-shaped obstacle below is about the breakup. The reason that the droplet is hollow is because the contact angle is 35 degrees therefore avoiding a lubricating film between the droplet and the wall.

Image of a droplet which is about to breakup due to an obstruction in the millichannel

Related interests

Povray modelling

The freely available finite element code Surface Evolver has a build-in module to convert simulation results into Povray format. Povray is a ray-tracing program which essentially allows the user to take a 'photograph' of a computationally defined structure. Liquid droplets on an incline are ideally suited for this, which resulted in the video below. Note that the pillars below the droplet are not to scale, but the water droplet shape itself is physically correct for a tilt angle of 25 degrees on a surface with large hysteresis.

Last modified: November 11 2015. © Delft University of Technology - TP group 2012