Prof. Dr.-Ing. Dr. h. c. Uwe Hampel

Experimental Thermal Fluid Dynamics
Phone: +49 351 260 2772

Dr. Markus Schubert
Phone: +49 351 260 2627

Experimental investigation of hydrodynamics in SiSiC foam packed reactors

Measurement system

The investigations of hydrodynamics in foam packed columns were carried out with the ultrafast electron beam X-ray computed tomography system ROFEX III. The measurements were carried out with a temporal resolution of 1 ms and a spatial resolution of 1 mm. Having two measurement planes with an axial distance of about 14 mm, the system provides a detailed insight in the morphology and statistical key parameters of the liquid pulses.

Micro CT images of the applied foams with pore densities of 20 ppi, 30 ppi and 45 ppi

Set-up of the ultrafast electron beam X-ray tomograph ROFEX III

Micro-CT images of the applied foams with pore densities of 20 ppi, 30 ppi and 45 ppi (from left to right) Schematical drawing of the ultrafast X-Ray scanner ROFEX III


Comparison pulse flow regime

Depending on operation conditions, partially and fully developed pulse flow ocurrs in solid foam packed reactors. Within the investigated measurement range pulse flow has been found at three gas/liquid velocity combinations (A, B, C) corresponding to gas and liquid superficial velocities uG and uL, respectively, of:

  • A: uL=0.03 m s-1 | uG=1.0 m s-1
  • B: uL=0.04 m s-1 | uG=0.8 m s-1
  • C: uL=0.04 m s-1 | uG=1.0 m s-1.

Varying operation conditions, the trend of cross sectional liquid saturation measured within solid foams can be seen in the following table.

Presentation pulse flow Presentation pulse flow Presentation pulse flow Scalebar for saturation images

20 ppi

30 ppi

45 ppi

The videos shown below are representative excerpts of one second length from a comprehensive set of experiments which provide insight in the complex dynamics of pulse flow. The data is presented in terms of liquid saturation βL, i.e. liquid volume per void fraction.