Contact

Dr. Sascha Heitkam

Head Foam and Froth Flows
s.heitkamAthzdr.de
Phone: +49 351 260 3925

Towards Fluid Dynamics of Foam and Froth

 
Emmy-Noether ©Copyright: DFG

Emmy Noether research group of Dr.-Ing. Heitkam, Sascha

funded by DFG, start: 05/2020

  

Motivation

Foam flow is not yet sufficiently understood because it is defined by the complex interaction of mechanisms at different length scales. At the same time, measurement techniques are scarcely available because established flow measurement techniques are not applicable to foam and froth.

Multi scale mechanism of foam flow ©Copyright: Dr. Heitkam, Sascha

Objectives

  • Develop and adapt measurement techniques for foam
  • Research foam flows in generic configurations
  • Identify and quantify unique flow features of foam

Measurement Techniques

  • X-ray Particle-Tracking-Velocimetry with custom-shaped 3D-printed tracer particles allows to measure the velocity distribution and vorticity inside a foam sample
X-ray particle tracking ©Copyright: Dr. Heitkam, Sascha
  • WIre-Mesh sensors with adapted calibration for measuring liquid fraction distribution with spatial and high temporal resolution

Foto: WMS in foam ©Copyright: Dr. Sascha Heitkam

  • Neutron radiography reveals liquid fraction as well as particle concentrations in foam and froth

Foto: Neutron Radiography of foam ©Copyright: Dr. Sascha Heitkam

  • Bubble size measurement by automated image segmentation and optical stress measurement

Foto: Bubble segmentation in foam ©Copyright: Dr. Sascha Heitkam

Foto: Stress measurement in foam ©Copyright: Dr. Sascha Heitkam


Generic foam flows

  • Flow around a cylinder in a vertical foam column

Foto: Foam flow around cylinder ©Copyright: Dr. Sascha Heitkam

  • Flow through nozzles and diffusors

Foto: Foam flow through a nozzle ©Copyright: Dr. Sascha Heitkam

  • Flow in a semi-annulus

Foto: Foam flow through an annulus ©Copyright: Dr. Sascha Heitkam


Foam features

  • Layered structure of bubbles near walls

Foto: Foam near wall ©Copyright: Dr. Sascha Heitkam

  • Anisotropic drainage in sheared foam

Foto: Anisotropic drainage in foam ©Copyright: Dr. Sascha Heitkam

  • Bubble size sorting in foam columns

Foto: radial foam bubble size ©Copyright: Dr. Sascha Heitkam

Publications

Knüpfer, L., Götzelt, R., Eckert, K., & Heitkam, S. (2024). Radial bubble size distributions in a rising foam column. Chemical Engineering Research and Design, 208, 336-347.

Skrypnik, A., Heitkam, S., Gerstenberg, C., Morelle, E., McHardy, C., & Rauh, C. (2024). Optical measurement of the shear stress and velocity distribution in an idealized deglutition process. Journal of Food Engineering, 365, 111849.

Knüpfer, L., Eckert, K., & Heitkam, S. (2024). A comparative study on the measurement of surface bubble size distributions in dry aqueous foams using optical methods. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 680, 132507.

Skrypnik, A., Cole, K., Lappan, T., Brito-Parada, P. R., Neethling, S. J., Trtik, P., ... & Heitkam, S. (2024). Neutron radiography of an anisotropic drainage flow. Physical Review E, 109(1), 014609.

Lappan, T., Herting, D., Ziauddin, M., Stenzel, J., Shevchenko, N., Eckert, S., ... & Heitkam, S. (2023). X-ray Particle Tracking Velocimetry in an Overflowing Foam. Applied Sciences, 13(3), 1765.

Skrypnik, A., Knüpfer, L., Trtik, P., Tholan, V., Parkes, S., & Heitkam, S. (2023). Neutron radiography of liquid foam structure near a vertical wall. Soft Matter, 19(44), 8552-8560.

Ziauddin, M., Schleicher, E., Trtik, P., Knüpfer, L., Skrypnik, A., Lappan, T., ... & Heitkam, S. (2022). Comparing wire-mesh sensor with neutron radiography for measurement of liquid fraction in foam. Journal of Physics: Condensed Matter, 35(1), 015101.

Knüpfer, L., & Heitkam, S. (2022). A machine learning approach to determine bubble sizes in foam at a transparent wall. Measurement Science and Technology, 33(6), 067001.

Heitkam, S., & Eckert, K. (2021). Convective instability in sheared foam. Journal of Fluid Mechanics, 911.

Lappan, T., Franz, A., Schwab, H., Kühn, U., Eckert, S., Eckert, K., & Heitkam, S. (2020). X-ray particle tracking velocimetry in liquid foam flow. Soft matter, 16(8), 2093-2103.

Heitkam, S., Lappan, T., Eckert, S., Trtik, P., & Eckert, K. (2019). Tracking of particles in froth using neutron imaging. Chemie Ingenieur Technik, 91(7), 1001-1007.