Practical trainings, student assistants and theses

Experimental investigation of two-phase flow on fixed valve trays for distillation columns (Id 317)

Bachelor theses / Master theses / Diploma theses / Compulsory internship

Foto: Eye-Catcher Single Valve ©Copyright: Dr. Philipp WiedemannDistillation columns are used for the thermal separation of multicomponent mixtures in the chemical industry. Owing to increased energy supply from renewable sources a more flexible operation of such apparatuses is already demanded. However, enlarged over- and under load modes are challenging with respect to design, since a high separation efficiency needs to be attained anyway. Especially in case of fixed valve trays there are presently no reliable methods for estimating the influence of the tray design on the complex two-phase flow of liquid and vapor. Therefore, a current research project aims at detailed investigations of the two-phase flow at single valves in order to evaluate their performance.
Within the frame of a student internship experimental investigations will be carried out using an existing lab-scale test rig. The phase distribution around the valve will be measured by specifically developed sensors. Further, particle image velocimetry will be used to capture the flow field of the liquid phase. Subsequently, measured data will be used to quantify and model the momentum transfer from the gas inlets to the liquid phase. The results will be used in future developments of numerical models to predict the two-phase flow on such trays.

Department: Experimental Thermal Fluid Dynamics

Contact: Dr. Wiedemann, Philipp

Requirements

  • studies in chemical/process/energy/mechanical engineering
  • interest in experimental work
  • creativity
  • good written and oral communication skills in English and German

Conditions

  • start: from Oct. 2021
  • working in a multi-disciplinary team
  • remuneration according to HZDR internal regulations

Links:

Online application

Please apply online: english / german

Druckversion


Construction and test of a reference measurement system for an industrial wire-mesh sensor for multiphase flow measurements (Id 313)

Bachelor theses / Diploma theses / Compulsory internship

Foto: reference measurements for multiphase measurement systems ©Copyright: Dr. Philipp WiedemannWire-mesh sensors allow for measuring the phase distribution of gas-liquid flows with high spatial and temporal resolution. For industrial applications (e.g. in power plants or chemical plants) previous projects already focussed on the development of data processing algorithms that convert the huge data sets into user friendly information, i.e. average void fraction and flow pattern. Hence, plant operators can now benefit from advanced process monitoring and operate their processes more efficiently.
The current developments focus on an enhanced system that includes online reference measurements in order to compensate drifts, which may result from changes of fluid properties when dealing with dynamic operation modes of the process. For this purpose, an existing concept should be converted into a final design, constructed and finally tested within the frame of an internship.

Department: Experimental Thermal Fluid Dynamics

Contact: Dr. Wiedemann, Philipp

Requirements

  • studies in process/energy/mechanical/electrical engineering
  • interest in practical work
  • creativity
  • good written and oral communication skills in English AND German

Conditions

  • start: immediately
  • working in a multi-disciplinary team
  • remuneration according to HZDR internal regulations

Links:

Online application

Please apply online: english / german

Druckversion


Modelling and Simulation of a Power-to-Gas process with ASPEN (Id 310)

Master theses / Diploma theses

Das Institut für Fluiddynamik des Helmholtz-Zentrums Dresden-Rossendorf (HZDR) beschäftigt sich unter anderem mit Fragen der Modellbildung und Simulation von verfahrenstechnisch eng gekoppelten Power-to-X-Systemen bestehend aus den Teilprozessen Hochtemperaturelektrolyse (Solid Oxide Electrolyzer Cells) und heterogen katalysierten Syntheseprozessen von Energieträgern der Zukunft (Methan, Methanol, usw.) unter stofflicher Nutzung anthropogener Kohlenstoffdioxidemissionen und regenerativ produziertem Strom. Mit Hilfe der Software Aspen Plus soll ein Prozessmodell des Sabatier-Prozesses zur Herstellung von Methan aus CO2 und H2 samt vorgeschalteter Hochtemperaturelektrolyse und aller relevanten peripheren Prozesskomponenten (Wärmetauscher, Kompressoren, Verdampfer, usw.) entwickelt werden.

Zur Realisierung dieser Aufgabe bietet die Abteilung Experimentelle Thermofluiddynamik für Studenten der unten genannten Studiengänge studienbegleitende Tätigkeiten zur beschriebenen Thematik an. Die Voraussetzung ist die Anfertigung einer Diplom- oder Masterarbeit.

Folgende Teilarbeiten sind durchzuführen:

  • Ausführliche Literaturrecherche zu den nachfolgenden Teilaufgaben,
  • Entwicklung eines stationären Prozessmodells einer Hochtemperaturelektrolysezelle samt relevanter Peripherie in Aspen Plus,
  • Entwicklung eines stationären Prozessmodells der Methanisierung von H2 und CO2 (Sabatier-Prozess) samt relevanter Peripherie in Aspen Plus,
  • Kombination beider Teilprozesse unter Berücksichtigung geeigneter Schnittstellen zu weiteren Prozessschritten,
  • Simulation und Validierung beider Teilprozesse und des Gesamtprozesses anhand von Literaturdaten.

Department: Experimental Thermal Fluid Dynamics

Contact: Fogel, Stefan

Requirements

  • Student(in) der Studiengänge Wirtschaftsingenieurwesen, Chemieingenieurwesen, Verfahrenstechnik, Energietechnik, Maschinenbau oder ähnlicher fachlicher Ausrichtung,
  • Idealerweise Erfahrungen/Kenntnisse in verfahrenstechnischer Modellierung in Aspen Plus,
  • Sorgfältige und selbstständige Arbeitsweise,
  • Freude an der wissenschaftlichen Arbeit.

Conditions

Bearbeitungszeit: 6 Monate (Beginn ab sofort möglich)

Online application

Please apply online: english / german

Druckversion


CFD simulation of gas-liquid flow in tray columns (Id 304)

Master theses / Diploma theses / Compulsory internship

Foto: Eye-Catcher ColTray-CFD ©Copyright: Sesi Preetam KotaTray columns are used for thermal separation of multicomponent mixtures in the chemical industry. Owing to increased energy supply from renewable sources a more flexible operation of such apparatuses is already demanded. However, enlarged over- and underload modes are challenging with respect to design. Basically, computational fluid dynamics provide a powerful support by predicting the complex two-phase flow on the tray. Nevertheless, further developments are particularly needed for valve trays in order to reliably simulate macroscopic flow scenarios.
Within the frame of a current research project we offer a student internship position for further development of a multi-phase CFD set-up that maps the individual gas inlets by point-like mass and momentum sources. Special focus is put on the influence of different valve geometries and experimental data is available from parallel student projects.

Department: Experimental Thermal Fluid Dynamics

Contact: Dr. Wiedemann, Philipp

Requirements

  • studies in chemical/process/energy/mechanical/computational engineering
  • substantiated knowledge in the field of CFD, preferably OpenFOAM
  • creativity
  • good written and oral communication skills in English and German

Conditions

  • start: from Nov. 2021
  • working in a multi-disciplinary team
  • remuneration according to HZDR internal regulations

Links:

Online application

Please apply online: english / german

Druckversion


Nonlinear characterization of horizontal gas-liquid flows (Id 266)

Master theses / Diploma theses / Compulsory internship

Foto: Nonlinear characterization of horizontal gas-liquid flows ©Copyright: Dr. Philipp WiedemannHorizontal gas-liquid flows occur in a variety of processes in energy and process engineering. According to the type of fluids, operating conditions and geometrical aspects different flow patterns are observed. These can be identified successfully by means of online monitoring systems when using appropriate measurement techniques and data processing algorithms.
Within the frame of an internship further investigations will focus on the predictability of the future development of the flow patterns on the basis of currently measured data. For that purpose, methods for characterizing nonlinear systems shall be realized as Matlab-scripts and applied to available data. Finally, the results are expected to be evaluated.

Department: Experimental Thermal Fluid Dynamics

Contact: Dr. Wiedemann, Philipp

Requirements

  • studies in mathematics/physics/engineering
  • interest in applying sophisticated mathematical methods to engineering problems
  • experiences in signal processing and nonlinear systems as well as using Matlab are beneficial
  • good written and oral communication skills in English and German

Conditions

  • start: from Okt. 2021
  • working in a multi-disciplinary team
  • remuneration according to HZDR internal regulations

Links:

Online application

Please apply online: english / german

Druckversion


Investigation of the flow behavior of fluidized particles by means of coupled CFD-DEM simulations (Id 253)

Master theses / Diploma theses / Compulsory internship

Foto: CFD-DEM fluidized bed ©Copyright: Dr. Philipp WiedemannFluidized beds are widely applied in process plants of pharmaceutical, food and chemical industries. Due to the complex flow structure optimization of such devices and process control is usually supported by simulations. However, since it is not feasible to resolve all spatial and temporal scales within a single simulation environment, large-scale simulations require reliable sub-models in order to account for small-scale phenomena correctly.
Therefore, the macroscopic flow properties of fluidized particles will be investigated by means of CFD-DEM simulations within the frame of an internship. Research will focus on the influence of different particle size distributions. The results shall lead to enhanced insight into the complex gas-solids-interaction of fluidized beds and will be incorporated into future developments.

Department: Experimental Thermal Fluid Dynamics

Contact: Dr. Wiedemann, Philipp

Requirements

  • studies in chemical/mechanical/process/computational engineering
  • substantiated knowledge in the field of CFD, preferably OpenFOAM
  • interest in multiphase flow phenomena
  • good written and oral communication skills in English and German

Conditions

  • start: from Oct. 2021
  • scope of work: up to 6 months (according to study regulations)
  • working in a multi-disciplinary team
  • remuneration according to HZDR internal regulations

Online application

Please apply online: english / german

Druckversion