Practical trainings, student assistants and theses

Investigation of the flow following behavior of lagrangian sensor particles in aerated reactors (Id 398)

Master theses / Diploma theses / Compulsory internship

Foto: Sensor particle next to stirrer with bubbles ©Copyright: Lukas BuntkielData acquisition in large industrial vessels such as bio reactor, biogas fermenters or wastewater treatment plants is limited to local measurement points due to the limited access to the vessel and the non-transparent fluid. To optimize these kinds of plants the three-dimensional flow field and the spatial distribution of e.g. temperature and electrical conductivity inside the vessel needs to be known. This can be done by the autonomous flow following lagrangian sensor particles (LSP) developed at the HZDR. Equipped with a pressure sensor, an accelerometer, two gyroscopes and a magnetometer, the sensor particle can track the flow movement inside of the vessels. From this, the flow field can be reconstructed.

To achieve a good flow following behavior, the density of the LSP can be adjusted before they are released into the vessel. While this works well for non-aerated systems, the influence of aeration on the flow following capability is unknown. Another unknown is how the velocities of the rising bubbles and of the continuous phase relates to the velocity measured by the LSP.
Therefore, the aim of this master thesis is to investigate the influence of aeration on the LSPs theoretically and experimentally by tracking the LSP with a camera. This includes the following tasks:

  • Literature research on flow following behavior of large particles in fluids
  • Experiments in a bubble column (330 mm ID) with LSPs and camera
  • Data evaluation to retrieve the fluid velocity, bubble rising velocity and LSP velocity
  • Comparison and conclusions on the flow following capability of LSPs in aerated reactors and comparison to the non-aerated case.

Department: Efficient wastewater treatment

Contact: Buntkiel, Lukas, Marchini, Sara

Requirements

  • Studies in the area of chemical or mechanical engineering or similar
  • Basic chemical and fluid engineering knowledge
  • Data analysis in Python
  • Independent and structured way of working

Conditions

  • Immediate start possible
  • Duration according to the respective study regulations

Links:

Online application

Please apply online: english / german

Druckversion


Numerical investigation of particle mixing - internship or thesis (Id 396)

Master theses / Diploma theses / Compulsory internship / Volunteer internship

Foto: Mixing of Fine Particles ©Copyright: Dr. Stephan BodenFine-grained solid particles from various industrial sources, which would otherwise be discarded, should ideally be processed to valuable products or inert residues. Among others, a) shredder fines from electronics and end-of-life vehicles, and b) flue dusts from non-ferrous metallurgical processes are of timely interest. They contain valuable residuals, such as metals, that can be returned to the industrial cycle instead of being landfilled. This is one aim of the Helmholtz project FINEST in which this work is embedded.
The different finest powders need to be mixed and agglomerated for further processing. Our work in the project deals with the granular mixing. One aim is to describe particle flow based on the rheology of the bulk good while describing the mixing process among the particles using a transport equation.
The particle bulk flow in a mixing apparatus can be modelled by CFD, using e.g. FEM. The particle flow field is then coupled with the transport equation to describe the mixing process among the particles.
We are looking for someone with experience in CFD or other modelling to tackle the implementation of this model. Expertise in the numerical development of in-house multi phase flow solvers is available [Lecrivain, JCP, 2021].

Department: Particle dynamics

Contact: Baecke, Anna Magdalena, Dr. Lecrivain, Gregory

Requirements

  • Student of e.g. Process Engineering, Chemical Engineering, Computational Engineering, Mechanical Engineering, …
  • General interest in fluid mechanics and simulations
  • Preliminary experience in CFD, ideally OpenFOAM
  • Preliminary experience in code development (C++) optional

Conditions

  • Immediate start possible
  • Duration of internship or thesis according to study regulations
  • Remuneration available, scholarship holders (e.g. ERASMUS+) welcome

Online application

Please apply online: english / german

Druckversion