Practical trainings, student assistants and theses
Direct numerical simulation of aerosol deposition in turbulent flows (Id 228)
Bachelor theses / Master theses / Diploma theses / Compulsory internship
The institute of fluids dynamics has been developing various numerical tools for the prediction of particle transport in flows. A distinguished feature of the institute lies in the deposition and resuspension of aerosol particles in turbulent flows. Our previous experimental and numerical studies showed that the deposition of aerosol particles is considerably increased in a turbulent flow evolving over a rough wall surface. Within the frame of a 6-month internship, a model will be implemented to randomly generate realistic three-dimensional terrains (height maps). Using an Euler-Lagrange approach the effect of the randomly generated wall roughness will be analyzed in detailed.
Department: Experimental Thermal Fluid Dynamics
Contact: Dr. Lecrivain, Gregory
Requirements
• Student with above average marks
• good programing skills
• good written and oral communication skills in English, German language is an asset (free classes are available on site)
Conditions
• 6-month internship
• Interest in multiphase flow phenomenas
Online application
Please apply online: english / german
Process intensification of multiphase reactors (Id 227)
Student practical training / Bachelor theses / Master theses / Diploma theses / Student Assistant
Multiphase reactors are widely used in the chemical industry. Especially, trickle bed reactors are advantageous, due to the high residence time, which compensate low diffusion rates. Examples are hydrogenations, aminations or oxidation of glucose.
Recently, a new multiphase reactor was developed to intensify the mass transfer by the superposition of rotation an inclination. To investigate the innovative reactor concept a modelling approach for the space-time-yield is necessary.
In the framework of a student thesis a reactor-particle model will be investigated via simulation studies. Additionally, further model improvements will be considered as the incorporation of heat balances. The simulations have to be executed in the MATLAB environment.
Department: Experimental Thermal Fluid Dynamics
Contact: Timaeus, Robert
Requirements
Studies in chemical engineering, process engineering or similar fields
Online application
Please apply online: english / german
Simulation Tools for Liquid Metal Batteries (Id 226)
Student Assistant
In contrast to conventional batteries, Liquid Metal Batteries feature all liquid anodes (alkali or earthalkalimetal), cathodes (transition metal or metal) and electrolytes (molten salts) at a temperature between 400 °C and 600 °C.
To simulate single cells and battery systems, a software package was developed (language: Python) at HZDR. This student assistant position is about the testing and documenting existing routines, and implementing new functions and routines.
The main topics are:
- Determination of the charge- and discharge behavior (electrical, thermal)
- Simulation of scenarios
- Optimization of energy and power density
- Geometrical-mechanical design and engineering
- Refinement of models and adaption to new cell chemistries
- Improivement of simulation times and storage management
Department: Magnetohydrodynamics
Contact: Dr. Nimtz, Michael
Requirements
Studies in chemistry, process engineering, mechanical engineering or physics, first experiences in programming (any language)
Conditions
Start: immediately
Duration: long-term
Links:
Online application
Please apply online: english / german
Design of a flexible Haber-Bosch process (Id 225)
Bachelor theses / Master theses / Diploma theses / Compulsory internship
As part of the Energiewende, the Institute for Fluid Dynamics at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is adapting energy intensive processes for the production of chemicals to be supplied only with electricity from renewable resources.
Ammonia is the second most produced chemical worldwide and the basis of all nitrogen-based fertilizers. Novel production paths include the combination of Haber-Bosch synthesis and water electrolysis.
The objective of the thesis is to model in Aspen Plus a Haber-Bosch process capable of operating with an intermittent energy supply, whether from renewable resources or from low priced electricity.
During the thesis, you are expected to perform the following tasks:
• Collect data on ammonia production using renewable energies and other flexible energy sources and its simulation.
• Design a dynamic Haber-Bosch process.
• Adapt the process for its operation with an intermittent energy supply.
• Assess the compatibility of the process with flexible water electrolysis and air separation.
Department: Experimental Thermal Fluid Dynamics
Requirements
• Student of Chemical, Process or Electrical Engineering, Energy Technology (Renewable Energy Systems) or similar.
• Experience with Aspen Plus, ChemCAD or similar
• High level of English.
Conditions
6 month, start immediately
Online application
Please apply online: english / german
Design of a flexible water electrolyzer (Id 224)
Bachelor theses / Master theses / Diploma theses / Compulsory internship
As part of the Energiewende, the Institute for Fluid Dynamics at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is adapting energy intensive processes for the production of chemicals to be supplied only with electricity from renewable resources.
Besides being the source of renewable-based hydrogen, water electrolysis is the key stage of all the Power-to-X processes and the production of commodities such as ammonia.
The objective of the thesis is to model in Aspen Plus a water electrolyzer process capable of operating with an intermittent energy supply, whether from renewable resources or from low priced electricity.
As part of the thesis, you are expected to perform the following tasks:
• Collect data on water hydrolysis using renewable energies and other flexible energy sources and its simulation.
• Design a dynamic electrolyzer.
• Adapt it for its operation with an intermittent energy supply.
• Assess the compatibility of the process with flexible air separation, ammonia synthesis (Haber-Bosch process).
• Evaluate its O2 generation potential.
Department: Experimental Thermal Fluid Dynamics
Requirements
• Student of Chemical or Process Engineering, Energy Technology (Renewable Energy Systems), or similar.
• Experience with Aspen Plus, ChemCAD or similar
• High level of English.
Conditions
6 month, start immediately
Online application
Please apply online: english / german
Design of a flexible pressure swing adsorption (PSA) process (Id 223)
Bachelor theses / Master theses / Diploma theses / Compulsory internship
As part of the Energiewende, the Institute for Fluid Dynamics at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is adapting energy intensive processes for the production of chemicals to be supplied only with electricity from renewable resources.
Air separation is the source of two diatomic molecules key to a number of industrial processes, O2, and N2. Pressure Swing Adsorption (PSA) is a process capable of producing N2 for erratic use patterns, and thus, a possible candidate for flexible operation.
The objective of the thesis is to model in Aspen Plus/Aspen Adsorption a PSA process capable of operating with an intermittent energy supply, whether from renewable resources or from low priced electricity.
The thesis project has the following aims:
• Collect data on air separationunits using renewable energies and other flexible energy sources and its simulation.
• Design a dynamic PSA process.
• Adapt it for its operation with an intermittent energy supply.
• Assess the compatibility of the process with flexible water electrolysis, and ammonia synthesis (Haber-Bosch process).
• Evaluate its O2 generation potential.
Department: Experimental Thermal Fluid Dynamics
Requirements
• Student of Chemical or Process Engineering, Energy Technology (Renewable Energy Systems), or similar.
• Experience with Aspen Plus, ChemCAD or similar
• High level of English.
Conditions
6 month, start immediately
Online application
Please apply online: english / german
Synthesis and characterization of isotope specific 'in-house standards' for the analysis of light and medium-heavy trace elements in natural minerals by secondary ion mass spectrometry (SIMS) and electron probe microanalysis (EPMA) (Id 222)
Master theses / Diploma theses
Secondary Ion Mass Spectrometry (SIMS) is a microanalytical method with a very good lateral and depth resolution combined with excellent limits of detection as well as a weak degree of destruction.
However, the method is very matrix sensitive and requires matrix adapted reference materials. Actually, there are no certified reference materials available for mineralogical studies. Therefore most SIMS labs use so-called ‘in-house’ standards.
The concentration of trace elements in minerals is of great economic importance as a quality parameter for raw materials. On the other hand, it bears very valuable genetic mineralogical information.
In collaboration with an industrial partner we will use the new method "energy-filter for ion implantation" as a tool for the production of matrix-matched reference materials (RMs) with a homogeneous trace element distribution in all three dimensions. These RMs will be used for SIMS and EPMA purposes.
The thesis project has the following aims:
• Determination of implantation possibilities for selected elements over the complete range of densities of naturally minerals using the available filters
• Calculation of the implantation parameters
• Experimental test of these parameters on selected minerals
• Test of the implantation by means of SIMS and EPMA
Department: Analytics
Contact: Dr. Renno, Axel
Requirements
• You study physics, material's sciences or engineering
• You are interested in mineralogical or analytical problems
• You are interested in modern analytical techniques
• You show initiative and good teamwork skills
Conditions
Start immediately
project period in accordance withe respective study regulations (est. 6 month)
Links:
Online application
Please apply online: english / german
Synthesis and characterization of isotope specific 'in-house standards' for the analysis of trace elements in natural quartz (SiO2) by secondary ion mass spectrometry (SIMS) and electron probe microanalysis (EPMA) (Id 221)
Master theses / Diploma theses
Secondary Ion Mass Spectrometry (SIMS) is a microanalytical method with a very good lateral and depth resolution combined with excellent limits of detection as well as a weak degree of destruction.
However, the method is very matrix sensitive and requires matrix adapted reference materials. Actually there are no certified reference materials available for mineralogical studies. Therefore most SIMS labs use so-called ‘in-house ’ standards.
The concentration of trace elements in natural quartzes is a very important quality parameter for the usage of these minerals as a raw material. On the other hand it bears very valuable genetic mineralogical information.
In collaboration with an industrial partner we will use the new method "energy-filter for ion implantation" as a tool for the production of matrix-matched reference materials (RMs) with a homogeneous trace element distribution in all three dimensions. These RMs will be used for SIMS and EPMA purposes.
The thesis project has the following aims:
• Determination of the implantable set of elements by using the available filters
• Calculation of the implantation parameters
• Experimental test of these parameters with selected combinations element – concentration – implantation depth
• Test of the implantation by means of SIMS and EPMA
Department: Analytics
Contact: Dr. Renno, Axel
Requirements
• You study physics, material's sciences or engineering
• You are interested in mineralogical or analytical problems
• You are interested in modern analytical techniques
• You show initiative and good teamwork skills
Conditions
Start immediately
project period in accordance withe respective study regulations (est. 6 month)
Links:
Online application
Please apply online: english / german
Entwicklung einer Handsteuerung für Kondensatorladegeräte (Id 216)
Student practical training
Die Handsteuerung eines Kondensatorladegerätes soll modernisiert werden. Das Kondensatorladegerät wird zur Untersuchung von Materialeigenschaften verwendet und erzeugt hohe Spannungen für das Laden von Kondensatoren.
Die Entwicklung der Handsteuerung beinhaltet unter anderem folgende Themen:
- Hardwareentwicklung (Schaltungsentwurf)
- Spezifikation/Recherche von Gehäuse-Optionen
- Softwareentwicklung (Mikrocontroller, Ansteuerung Display)
Institute: Department of Research Technology
Contact: Winkler, Nick, Wagner, Nicole
Requirements
- Grundkenntnisse Elektrotechnik
- Grundkenntnisse C
Online application
Please apply online: english / german
Numerical simulation of adiabatic two-phase flow in horizontal elbow bends (Id 215)
Bachelor theses / Master theses / Diploma theses / Compulsory internship
The transport of fluids is an essential part of many different industrial processes. Particularly gas-liquid flows play an important role in the field of power plant technology, pipeline design, multi-phase reaction engineering and separation processes such as distillation or extraction units.
The flow morphology, the degree of dispersion and the phase fraction are important input parameters for the design of downstream process equipment. In contrast to two-phase flow in vertical and horizontal two-phase flow the influence of complex pipe modifications on the flow is not well described.
Numerical methods are usually used to obtain detailed 3D information on the characteristics of the flow parameters, while simultaneously being flexible towards geometries and operational conditions.
This work aims on implementing gas-liquid two-phase flow in elbow bends using CFX.
Tasks:
• Literature analysis on two-phase CFD modelling in pipes
• Implementation of a gas-liquid two-phase flow in elbow bend using CFX
• Flow simulation and characterization of the two-phase flow up- and downstream of the bend; comparison with available experimental data
Institute: Institute of Fluid Dynamics
Contact: Döß, Alexander, Dr. Höhne, Thomas
Requirements
• Background in process engineering, chemical engineering, mechanical engineering or related disciplines.
• Knowledge in the field of fluid dynamics or modelling are desirable
Conditions
Process time: 4 - 8 months
Start immediately
Online application
Please apply online: english / german
Synthesis of Upconverting Nanoparticles as biomedicinal imaging probes (Id 213)
Master theses / Diploma theses / Student Assistant / Compulsory internship / Volunteer internship / Research Assistant
The Department of Radionuclide Theragnostics (https://www.hzdr.de/db/Cms?pNid=2629) offers a position for the following topic: "Synthesis of Upconverting Nanoparticles as biomedicinal imaging probes" The position will be available from mid of January 2019. The employment contract is flexible, but limited to a maximum of 3 months for full-time position. The topic can be part of master thesis.
Upconverting nanoparticles (UCNPs) are lanthanide-doped photoluminescent nanomaterials, which exhibit the upconversion of photons. They absorb two or more near-infrared photons and emit them to higher energy. Due to their excellent (long-lived and anti-Stokes) luminescence properties, low cytoxicity and photostability, UCNPs are promising candidates for biomedical applications acting as luminescent imaging probes. The colour output can be easily tuned by lanthanide ions (“activators”). In addition, a tailor-made surface functionalisation strategy gives not only the opportunity to make them water-dispersible but also to attach tumour-specific molecules (e.g. peptides, antibodies,…).
The work aims to provide ultrasmall upconverting nanoparticles (<10 nm) using well-established protocols from our group– with focus on the size, luminescence properties and stability. Our group (https://www.hzdr.de/db/Cms?pNid=499) offers years of experience and excellent skills dealing with the synthesis, characterisation as well as surface functionalisation startegies of nanoparticles.
We are looking forward to your application!
Department: Radionuclide Theragnostics
Contact: Dr. Kubeil, Manja
Requirements
• Degree in chemistry with good marks
• Experimental skills in synthesis and characterization of nanoparticles
• Experience with Schlenk-technique/ working under inert atmosphere
• personal commitment, ability to work in a team
• good written and oral communication skills in English
Conditions
• Flexible working hours
• Full- or part-time possible
Online application
Please apply online: english / german
Beiträge zur Weiterentwicklung der ultraschnelle Röntgencomputertomografie (Id 212)
School practical training / Master theses / Diploma theses
Die im Institut für Fluiddynamik am HZDR entwickelte Ultraschnelle Röntgencomputertomografie wird bei der Beforschung von Strömungsvorgängen auf einer Vielzahl von Themengebieten als berührungsloses, bildgebendes Messverfahren genutzt. Dabei wird mit Hilfe eines freien Elektronenstrahls, der durch Magnetfelder im Vakuum geführt wird, eine um das Messobjekt rotierende Röntgenstrahlungsquelle erzeugt. Aus den vom Detektor synchron aufgenommenen Projektionsdatensätzen werden 2D-Schnittbildsequenzen der Schwächungsverteilung im Messobjekt mit hoher räumlicher und sehr hoher zeitlicher Auflösung generiert. In den letzten Jahren wurden die bestehenden ROFEX-Scanner stetig verbessert. Gleichwohl besteht Entwicklungspotential im Bereich des Monitorings der Röntgenquellposition, d.h. des Fokuspunkts des Elektronenstrahls, da dieser sehr empfindlich auf Störeinflüsse, wie zum Beispiel parasitäre Magnetfelder, reagiert. Schlussendlich wäre eine aktive, dynamische Nachjustage des Elektronenstrahls das Entwicklungsziel.
Im Rahmen dieser Arbeit sollen zunächst Konzepte für ein in-situ Strahlbahnmonitoring entwickelt und bewertet werden. Für das erfolgversprechendste Konzept soll ein Realisierungsvorschlag bis hin zur Auslegung notwendiger Komponenten erarbeitet werden. Ein praktischer Test ist wünschenswert, wenn in der Zeit möglich.
Teilaufgaben:
• Theoretische Entwicklung der Monitoring-Konzepte / Literaturstudium
• Grundsätzliche Berechnungen; evtl. Simulationen
• Aufbau eines Demonstrators bzw. Test am ROFEX-Scanner
Infos zu ROFEX-Scanner: https://www.hzdr.de/db/Cms?pOid=30242&pNid=0
Department: Experimental Thermal Fluid Dynamics
Contact: Dr. Barthel, Frank
Requirements
• Studium der Elektrotechnik/Physik/Maschinenbau
• Strukturierte, selbstständige Arbeitsweise
• Technische Kreativität und Gestaltungswille
• Fundierte Kenntnisse in Automatisierung und Konstruktion
Online application
Please apply online: english / german
Beiträge zu innovativen Konzepten für die ultraschnelle Röntgencomputertomografie (Id 211)
Student practical training / Master theses / Diploma theses
Die im Institut für Fluiddynamik am HZDR entwickelte Ultraschnelle Röntgencomputertomografie wird bei der Beforschung von Strömungsvorgängen auf einer Vielzahl von Themengebieten als berührungsloses, bildgebendes Messverfahren genutzt. Dabei werden aus Projektionsdatensätzen 2D-Schnittbildsequenzen mit hoher räumlicher und sehr hoher zeitlicher Auflösung generiert. In den letzten Jahren wurden die bestehenden ROFEX-Scanner stetig verbessert. Gleichwohl besteht ein hohes Entwicklungspotenzial im Bereich der Röntgenstrahlungserzeugung.
Im Rahmen dieser Arbeit sollen Schlüsselexperimente auf dem Gebiet der schnell gepulsten Röntgenstrahlungserzeugung geplant und durchgeführt werden.
Teilaufgaben:
• Literaturstudium zu gesteuerter bzw. provozierter Feldemission
• Grundsätzliche Berechnungen; evtl. Simulationen
• Aufbau eines Demonstrators und Experimente zur getakteten Erzeugung von Röntgenstrahlung
Infos zu ROFEX-Scanner: https://www.hzdr.de/db/Cms?pOid=30242&pNid=0
Department: Experimental Thermal Fluid Dynamics
Contact: Dr. Barthel, Frank
Requirements
• Studium der Elektrotechnik/Physik/Maschinenbau
• Strukturierte, selbstständige Arbeitsweise
• Technische Kreativität und Gestaltungswille
• Konstruktionsfähigkeiten
Online application
Please apply online: english / german
Optimization of the design and the operation of liquid metal batteries (Id 205)
Student practical training / Bachelor theses / Master theses / Diploma theses / Compulsory internship
In contrast to conventional batteries, Liquid Metal Batteries feature all liquid anodes (alkaline or alkaline earth metal), cathodes (transition metal or metal) and electrolytes (molten salts) at a temperature between 400 °C and 600 °C.
The technical design of a liquid metal battery system (elctrodes, electrolyte, current collector, cell container and electrical and mechanical connections) and the operational parameter of such a system are connected in a complex manner and need to fulfil a number of auxiliary conditions.
For such a system, a multi-objective optimization shall be implemented and applied. He goal is to optimize the whole system in terms of energy efficiency, material usage and overall size for arbitrary power ratings/capacities and different load cycles.
Starting point is an existing model of a battery system in Python.
Department: Magnetohydrodynamics
Contact: Dr. Nimtz, Michael, Dr. Weier, Tom
Requirements
Study of mechanical engineering, physics, mathematics or similar
Basic knowledge of engineering principles.
Good knowledge of a programming language, preferably python.
Conditions
Start: from now
Duration: 4-6 months
Links:
Online application
Please apply online: english / german
Looking for treasures inside rocks: from 2D to 3D (Id 204)
Bachelor theses / Master theses / Diploma theses
2-dimensional imaging of surfaces is the preferred method to analyse the microstructure of rocks for industrial and academic research. The main advantages of 2D imaging are the high resolution and the possibility to analyse the chemical and phase composition of surfaces. However, it is inaccurate to extrapolate bulk quantitative information from the inside of a rock based on just looking at its surface.
This project aims to develop the first experimental procedures to correlate quantitative 3D imaging (computed tomography, CT) with high resolution chemical 2D imaging (e.g. electron microscopy, SEM / MLA, and spectroscopy). You will gain hands on experience on these techniques and sample preparation. You are expected to develop the experimental workflow and to optimize the image analysis to achieve the best correlation between 2D and 3D imaging. This correlation will allow you to identify the valuable minerals and their 3D properties inside rocks from mining sites and ore processing plants.
Department: Analytics
Contact: da Assuncao Godinho, Jose Ricardo, Dr. Renno, Axel
Requirements
- Student of geology, mineralogy, material sciences or related areas
- Good spoken and written English
- Enthusiasm for experimental lab. work
- Creativity and desire to do new things
Conditions
- start any time
Links:
Online application
Please apply online: english / german
Programmierung einer Tellerradsteuerung mit TwinCAT 3 (Id 203)
Student practical training / Bachelor theses
Am Zentrum für Ionenstrahlphysik wird eine bestehende Implantationskammer modernisiert. Für die Instrumentierung wird ein Steuerungssystem der Firma Beckhoff verwendet, welches eine Vakuumsteuerung und die Steuerung eines Tellerrades mit einem Servo-Motor realisieren soll.
Die Arbeit umfasst u.a. folgende Themen:
- Einbindung von Anlagen-I/O in die Steuerung
- Programmierung von Abläufen für das Vakuum
- Ansteuerung des Motors und Anfahren von dedizierten parametrierbaren Positionen
- Realisierung einer benutzerfreundlichen Visualisierung direkt auf der Steuerung
- Test und Inbetriebnahme der Steuerung
Institute: Department of Research Technology
Contact: Wagner, Nicole
Requirements
- Grundlagen der Automatisierungstechnik
- Programmiererfahrung im Bereich SPS-Steuerungen (vorzugsweise TwinCAT)
Conditions
- Bearbeitungszeit: 4-6 Monate
- Beginn: ab sofort
Online application
Please apply online: english / german
Analysis of Liquid Metals by Laser Induced Breakdown Spectroscopy LIBS (Id 202)
Student practical training / Bachelor theses / Master theses / Diploma theses / Compulsory internship / Volunteer internship
The expansion of renewable energies requires innovative systems for the efficient storage and conversion of energiy. The HZDR investigates how liquid metals can be used in Liquid Metal Batteries (LMB) and thermoelectric converters (Alkali-Metal Thermo-Electric Converter – AMTEC). These system are promising candidates for future grid storages and waste heat utilisation, respectively.
In both systems, metal alloys and intermetallic phases of reactive alkali metals (lithium, potassium, sodium) are formed. Within this work, these alloys will be analysed and characterised by LIBS (Laser Induced Breakdown Spectroscopy). LIBS is a type of emission spectroskopy, where laser ablated and excited sample particles are analysed. The aim is to determine the cell performance on the basis of the state of charge and health, respectively, and derive corresponding measures for optimisation.
Work packages include:
- Characterisation of measured spectra by multivariate analysis
- Development of a suitable evaluation tool
- Preparation of reference samples and analysis of reproducibility
- Method development for sample taking and preparation
Department: Magnetohydrodynamics
Contact: Dr. Kubeil, Clemens, Dr. Weier, Tom
Requirements
• Interest in scientific and experimental work
• Knowledge of analytical techniques (ideally emission spectroscopy)
• Knowledge of spectra evaluation / multivariate analysis / progamming
• good to very good marks
Conditions
• starts immediatly
• duration: 3-6 months
• only application with CV and certificates will be considered
Online application
Please apply online: english / german
Simulation of ion optical behaviour of ions in the mass range between 1 and 300 amu during coupling of a SIMS instrument with a tandem accelerator (Id 200)
Master theses / Diploma theses
Actually, a Super-SIMS-Set-up is developed at the HZDR Ion Beam Centre (IBC) by connecting a conventional SIMS-source (SIMS = Secondary ion mass spectrometry) to a 6 MV tandem accelerator. Due to the acceleration of the extracted secondary ions to MeV-energies and their charge reversal from negative to positive ions, Super-SIMS can reach about 2 to 3 orders of magnitude lower detection limits (up to 10-12 or ppt, highly depending on analyte and matrix) as conventional SIMS.
The CAMECA 7fauto SIMS spectrometer is coupled by means of a 30 kV potential to the 6MV tandem accelerator. This potential is needed to fulfil the acceptance conditions of the accelerator. The beam transfer from the SIMS, seen as an ion source, to the entrance lens differs individually for every type of ion (mass and energy) and needs to be studied systematically.
The aim of the thesis is a systematic survey of all possible negative secondary ions (masses 1 – 300) in the energy range of the connection ion optics. The method of simulation will be SIMION® (http://simion.com/) an ion optical modelling and calculation software.
Department: Analytics
Contact: Dr. Renno, Axel, Dr. Rugel, Georg
Requirements
• interest in modern analytical techniques
• student of physics
• experiences in simulation calculations
• You show initiative and good teamwork skills
Conditions
start: immediately
Links:
Online application
Please apply online: english / german
Ion beam transport calculations for Super-SIMS project (Id 199)
Master theses / Diploma theses
Actually, a Super-SIMS-Set-up is developed at the HZDR Ion Beam Centre (IBC) by connecting a conventional SIMS-source (SIMS = Secondary ion mass spectrometry) to a 6 MV tandem accelerator. Due to the acceleration of the extracted secondary ions to MeV-energies and their charge reversal from negative to positive ions, Super-SIMS can reach about 2 to 3 orders of magnitude lower detection limits (up to 10-12 or ppt, highly depending on analyte and matrix) as conventional SIMS. To understand and optimize the ion-optics needed for these challenging project calculations should be performed. All the existing hardware at the IBC, like einzel lenses, quadrupoles, magnets have to be implemented in the calculation. The tool to perform and visualize the ion optic calculations will be LIMIOPTIC (www.limioptic.de), which was built for the CologneAMS (http://www.cologneams.uni-koeln.de/) system similar to the setup DREAMS at the IBC. The results of these calculations have to be compared with real machine settings and used for improvement of the transmission parameters of the whole system.
Department: Analytics
Contact: Dr. Renno, Axel, Dr. Rugel, Georg
Requirements
• interest in modern analytical techniques
• student of physics
• experiences in simulation calculations
• You show initiative and good teamwork skills
Conditions
start: immediately
Links:
Online application
Please apply online: english / german
Simulation of the critical time line of ions in the mass range between 1 and 300 amu in a Super-SIMS setup (Id 198)
Master theses / Diploma theses
Actually, a Super-SIMS-Set-up is developed at the HZDR Ion Beam Centre (IBC) by connecting a conventional SIMS-source (SIMS = Secondary ion mass spectrometry) to a 6 MV tandem accelerator. Due to the acceleration of the extracted secondary ions to MeV-energies and their charge reversal from negative to positive ions, Super-SIMS can reach about 2 to 3 orders of magnitude lower detection limits (up to 10-12 or ppt, highly depending on analyte and matrix) as conventional SIMS.
The basis for a coordinated control software between ion source (SIMS instrument), accelerator and the detectors of the high-energy mass spectrometer is a sound knowledge of the flight time of ions in the mass range between 1 and 300 amu and the complete energy range on the low and high-energy side.
The aim of the thesis is the establishment of a small software tool which allows the simulation of the critical time line of given ions in a broad range of ion optical conditions. The simulation should base on ion optical simulations done with the LIMIOPTIC (www.limioptic.de) and SIMION® (http://simion.com/) codes.
It is the intention that the software tool runs either independently or could be integrated in the future control software of the Super-SIMS.
Department: Analytics
Contact: Dr. Rugel, Georg
Requirements
• interest in modern analytical techniques
• student of physics or informatics
• programming skills
• You show initiative and good teamwork skills
Conditions
start: immediately
Links:
Online application
Please apply online: english / german
Smart actuation system for flow following µAUV particles for industrial process environments (Id 175)
Master theses / Diploma theses / Compulsory internship
Smart flow following sensor particles are used for acquisition of spatially distributed process parameters in industrial processes, such as biogas digesters, waste water treatment basins or bioreactors. The aim of the work is the development of an actuator concept for sensor µAUV-particles for the automatic adjustment of buoyancy (buoyancy) and for buoyancy maneuvers under the condition of small size, minimum energy consumption and high reliability. For this, alternative physical and chemical mechanisms should be considered based on the existing electromechanical solution. There are suitable variants to implement and test. Furthermore, the development of sensor intelligence for the actuators in the sensor particles is an essential part of the task. The developed concepts have to be validated experimentally.
We cordially invite you to an on-site conversation to introduce the topic and to agree on further details. Do not hesitate to contact us, because the way is worth it for you.
What can you expect:
In our department, we offer you an attractive work environment to expand your personal and professional skills. The insight into the diverse R&D projects of the department in the areas of sensor and measuring technology as well as energy and process engineering (among others) and the excellent technical equipment of the laboratories offer optimal conditions for this. The possibility of close contact with competent experienced colleagues plays a central role. As part of student work, we have pursued the approach of structured supervision and associated constructive feedback. This includes regular meetings with your supervisor and intermediate presentations in the form of informal "workshop reports" in the extended audience of interested individuals of the department in order to optimally support you in the successful completion of your project. Furthermore, we are open to support outstanding candidates in their continuing academic qualification, such as in doctoral scholarships or in current or upcoming R&D projects.
Subject-related task spectrum:
• Establishment of the scientific and technical principles of mechanical, physical and chemical principles of action for embedded, actuating components
• Concept development for actuators for taring of sensor particles
• Development of sensor intelligence for situation-dependent, automatic buoyancy, for buoyancy maneuvers and for recovery
• Selection, purchase/ composition and comparison of solution variants
• Minimization of size and energy consumption
• Increased reliability when used in particle-loaded biological substrates
• Development of firmware taking into account existing function routines based on an embedded system with 32-bit data structure (e.g. STM32)
• Conception and realization of suitable test scenarios
• Characterization and comparison of implemented variants with regard to accuracy of taring and reliability in long-term use
Department: Experimental Thermal Fluid Dynamics
Contact: Dr. Reinecke, Sebastian
Requirements
• Studies in electrical engineering, mechatronics, mechanical engineering and similar engineering courses
• Experience in design and (micro) actuator systems
• Experience in programming microcontrollers for embedded systems (e.g. STM32)
• Experience in control electronics for microdrives and board design for embedded systems
• Fundamentals of (micro) actuator systems, movement of rigid bodies, measurement uncertainties, digital signal processing
• Data analysis optionally in Matlab, Octave or C / C ++
• Independent, self-responsible working method
Links:
Online application
Please apply online: english / german
Development of new absorber layers for concentrated solar tower plants (Id 173)
Bachelor theses / Master theses / Diploma theses
Turmkraftwerke stellen die neueste Generation von Anlagen zur solarthermischen Elektroenergieerzeugung dar. Extrem konzentriertes Sonnenlicht wird dabei auf einen zentralen Absorber gerichtet, der die Wärme auf eine Wärmeträgerflüssigkeit überträgt. Zur Erhöhung des Wirkungsgrades von Turmkraftwerken muss die Arbeitstemperatur des Wärmeträgers von derzeit maximal 550°C auf 800°C erhöht werden. Dafür benötigt man neuartige Absorberschichten, deren Funktionalität unter den herrschenden Bedingungen 25 Jahre lang erhalten bleibt.
Inhalte dieser Abschlussarbeit sollen primär die gezielten PVD-Abscheidungen und deren Charakterisierungen mit modernsten in situ und ex situ Analysemethoden sein. Zur Abscheidung stehen verschiedene PVD-Verfahren zur Verfügung.
Department: Nanocomposite Materials
Contact: Dr. Krause, Matthias
Requirements
1. Studium der Werkstoffwissenschaften, Physik oder Chemie
2. Interesse und Freude an experimenteller wissenschaftlicher Arbeit
3. Gute Kenntnisse in Programmierung und Datenverarbeitung
4. Fließendes Englisch
Conditions
Beginn: 1.1.2018 (frühestens), internationale Forschungsumgebung, ortsübliche Aufwandsentschädigung
Die Arbeit wird im Rahmen eines EU-RISE-Projektes (GA 645725) in Zusammenarbeit mit 4 Partnern im EU-Ausland angefertigt.
Online application
Please apply online: english / german
Liquid flow characterization on distillation column trays (Id 169)
Student practical training / Master theses / Diploma theses / Student Assistant
Distillation is highly important in chemical process industries, as 95% of the worldwide separations use this technology in large industrial columns. Increasing energy costs and higher awareness for environmental concerns motivate towards the optimization of the performance of tray columns. Flow and mixing patterns in the tray columns have strong influence on their separation performance. Plug flow is considered ideal, while any deviations from plug flow are referred as non-idealities that are detrimental to the tray efficiency.
Mathematical models are used to assess the flow patterns and predict the tray efficiency. For this purpose, precise identification of the flow patterns and the hydraulic parameters at high spatio-temporal resolution is a prerequisite. An in-house developed sensor specifically designed for the cross-flow trays will be used in three-dimensional framework. Proper sensor calibration and data processing is essential for the accuracy of the measurements. Further, the flow visualization and determination of the hydraulic parameters need to be achieved through MATLAB scripts.
Department: Experimental Thermal Fluid Dynamics
Contact: Vishwakarma, Vineet
Requirements
1. Academic studies in chemical engineering, process engineering or similar field, with reasonable understanding of mathematics and distillation columns.
2. Enthusiasm for experimental work, with good interpersonal skills.
3. Programming skills: MATLAB.
Conditions
The candidate can start at the earliest. The duration of the project can be up to 6 months. The candidate will be invited for interview and discussion, or may be asked to give a short presentation before the selection.
Links:
Online application
Please apply online: english / german
Entwicklung eines digitalen Lock-in-Verstärkers auf FPGA-Basis (Id 166)
Student practical training
Das Prinzip des Lock-In-Verstärkers erlaubt es empfindliche Messgeräte zu realisieren. Im vorliegenden Projekt soll die Umsetzung auf Basis digitaler Signalverarbeitung im FPGA erfolgen. Dabei sollen u.a. Erfahrungen bezüglich erreichbarer Performance und des nötigen Implementierungsaufwandes gewonnen werden.
Institute: Department of Research Technology
Contact: Lange, Bert
Requirements
- Studium der Elektrotechnik oder Informatik
- Interesse an digitaler Signalverarbeitung
- Grundkenntnisse im Einsatz von FPGAs
- Grundkenntnisse VHDL erforderlich
Online application
Please apply online: english / german
Bestimmung von Geschwindigkeitsfeldern aus tomographischen Bilddaten mittels Kreuzkorrelation (Id 164)
Bachelor theses / Master theses / Diploma theses
Am Institut für Fluiddynamik am Helmholtz-Zentrum Dresden-Rossendorf sind zahlreiche Messverfahren für die Untersuchung von Mehrphasenströmungen entwickelt worden. Eines davon ist die ultraschnelle Elektronenstrahl-Röntgen-Computertomographie, welche mit Aufnahmeraten von bis zu 8000 Bildern pro Sekunde eine dedizierte Aufklärung von Strömungsstrukturen erlaubt. Aufgrund der quasi simultanen Aufnahme von Bilddaten aus zwei Messebenen ergibt sich zudem die Möglichkeit, axiale Geschwindigkeiten zu bestimmen, wofür üblicherweise Kreuzkorrelationsverfahren verwendet werden. Im Rahmen dieser Arbeit sollen die Möglichkeiten dieser Methodik in Hinblick auf die Bestimmung von Geschwindigkeitsfeldern in verschiedenen Strömungsszenarienn analysiert werden.
Folgende Teilaufgaben sind zu lösen:
• Studie zu verschiedenen Varianten der Kreuzkorrelation
• Simulation verschiedener Szenarien und Bewertung der Genauigkeit
• Übertragung der Ergebnisse auf reale Messungen
Department: Experimental Thermal Fluid Dynamics
Contact: Dr. Bieberle, Martina
Requirements
• Studium der Informatik, Mathematik oder einer Ingenieurwissenschaft
• Interesse an Messverfahren und Datenanalyse
• Selbständiges Arbeiten
Conditions
Bearbeitungszeit 4 bis 6 Monate
Links:
Online application
Please apply online: english / german
Analytische und numerische Vorhersage von magnetohydrodynamischen Grenzflächeninstabilitäten in Flüssigmetallbatterien (Id 161)
Master theses / Diploma theses / Research Assistant
Der vermehrte Ausbau erneuerbarer Energien in Deutschland erfordert mit zunehmender Wichtigkeit die Integration effizienter stationärer Netzspeicher, da Solar- und Windenergie wetterbedingt stark fluktuieren. Adäquate Netzspeicher sollten in der Lage sein, möglichst kostengünstig überschüssige Energie punktuell zu speichern und nach Bedarf wieder in das Stromnetz zu speisen. Ein vielversprechender Kandidat für diese Anforderungen sind Flüssigmetallbatterien. Flüssigmetallbatterien bestehen aus zwei flüssigen Metallen (z. B. Na, Bi), welche durch einen ebenso flüssigen Elektrolyten (z. B. NaCl) getrennt sind. Alle drei Phasen schwimmen übereinander. Beim Entladen gibt das Na ein Elektron ab, wandert als Ion durch den Elektrolyten und legiert mit dem unteren Metall zu NaBi.
Um Flüssigmetallbatterien kostengünstig betreiben zu können, müssen sie möglichst groß gebaut werden. Dadurch werden sie jedoch anfällig für diverse Strömungsinstabilitäten wie thermischer Konvektion oder Elektrowirbelströmungen, welche den sicheren Batteriebetrieb gefährden und im schlimmsten Fall zum Aufreißen des Elektrolyten (Kurzschluss) führen können.
Als besonders signifikant haben sich in den letzten Jahren Grenzflächeninstabilitäten in den Elektrolyt-Metall Grenzflächen herauskristallisiert, welche von magnetohydrodynamischen Wechselwirkungen getrieben werden und rotierende Grenzflächenwellen in der Batterie anregen (siehe Abbildung).
Im Rahmen dieser Master- oder Diplomarbeit sollen die einzelnen destabilisierenden Mechanismen, je nach Neigung des Bewerbers, analytisch und/oder numerisch erfasst und quantifiziert werden, um Stabilitätskriterien zur Gewährleistung der Betriebssicherheit von Flüssigmetallbatterien abzuleiten. Dafür sollen mathematische Werkzeuge der linearen Stabilitätsanalyse sowie störungstheoretische Methoden zum Einsatz kommen.
Konkret können eine oder mehrere der folgenden Aufgaben in Angriff genommen werden:
- Durchführung linearer Stabilitätsanalysen auf bereits bekannte Differentialgleichungen formuliert in verschiedenen Näherungen
- Entwicklung oder Weiterentwicklung neuer analytischer Modelle zur effizienten Beschreibung von Grenzflächeninstabilitäten
- Analytische Beschreibung der Grenzflächenkopplung in mechanisch angeregten drei-Schicht-Systemen zum experimentellen Vergleich (Ansatz bereits vorhanden)
- Optimierung der elektrischen Randbedingungen zur Stabilisierung der Batterie unter Verwendung von Variationsrechnungen oder Simulationen
- Durchführung numerischer Parameterstudien
Department: Magnetohydrodynamics
Contact: Horstmann, Gerrit Maik, Dr. Weier, Tom
Requirements
- Studium im Bereich Physik, Mathematik oder Maschinenbau mit theoretischem Hintergrund und guten bis sehr guten Noten
- Kenntnisse der (theoretischen) Strömungsmechanik und idealerweise Grundkenntnisse der Elektrodynamik
- Ausgeprägte analytische Fähigkeiten und Spaß an komplexen Aufgabenstellungen
- Vertrauter Umgang mit der Vektoranalysis
- Programmierkenntnisse (Python, Matlab, C++, etc.)
- Kenntnisse der linearen Wellentheorie vom großen Vorteil
Erfahrungen in einem der folgenden Bereiche wünschenswert, jedoch keine Voraussetzung:
- Methoden der linearen Stabilitätsanalyse
- Potentialtheorie
- Flachwassertheorie
- Euler-Lagrange Optimierungen (analytische Mechanik)
Conditions
Beginn: ab sofort
Dauer: >= 6 Monate
- Gute Betreuung von der intensiven Einarbeitung bis hin zur Verfassung der Abschlussarbeit
- Vergütung
- Angenehmes kollegiales Umfeld
Online application
Please apply online: english / german
Untersuchungen zur Steigerung der Energieeffizienz von Belüftungselementen für die Anwendung in der biologischen Abwasserreinigung (Id 154)
Student practical training / Bachelor theses / Master theses / Diploma theses / Student Assistant
Die biologische Abwasserbehandlung leistet einen wesentlichen Beitrag zum Erhalt der Gewässerqualität. Im kommunalen Bereich entfällt ein großer Anteil des Gesamtenergiebedarfs auf die Kläranlagen. In diesen Anlagen wird oft mehr als 50 % der elektrischen Energie für den Eintrag von Luft in Belebungsbecken benötigt, in denen Mikroorganismen die im Abwasser enthaltenen Nährstoffe unter Verbrauch von Sauerstoff zersetzen.
Nach aktuellem Stand der Technik wird die Luft durch Belüftungselemente wie Membran- oder Keramikbelüfter eingetragen. Ein Teil der für den Lufteintrag benötigten Energie wird entweder für die Dehnung der schlitzförmigen Öffnungen der Membranen oder zur Überwindung des Strömungswiderstandes in der Keramikwand aufgewendet.
Neue Konzepte sollen diesen Energiebedarf reduzieren und für einen optimierten Sauerstoffeintrag in das Belebungsbecken sorgen.
Department: Experimental Thermal Fluid Dynamics
Contact: Herrmann-Heber, Robert
Requirements
• Studium im Bereich Verfahrenstechnik, Chemie-Ingenieurwesen und ähnlichen Ingenieurstudiengängen
• Freude am experimentellen Arbeiten
Conditions
• 4-6 Monate
• Ab September/Oktober
Online application
Please apply online: english / german
Student assistant at the DeltaX School Lab (Id 95)
Student Assistant
Das Schülerlabor DeltaX macht die Forschung am Helmholtz-Zentrum Dresden-Rossendorf für Schülerinnen und Schüler erlebbar. Für ihre Betreuung und Unterstützung beim Experimentieren suchen wir Studierende, die Freude an der Vermittlung von Naturwissenschaften, Forschung und Technik haben. Bewerben Sie sich als studentische Hilfskraft im Schülerlabor DeltaX und werden Sie Teil eines jungen und aufgeschlossenen Teams.
Das Schülerlabor DeltaX bietet Schulklassen Experimentiertage zu den Themen:
- „Licht und Farbe“ (Klassen 5-10)
- „Magnetismus und Materialforschung“ (ab Klasse 10)
- „Radioaktivität und Strahlung“ (ab Klasse 9)
- NEU ab dem SJ 2019/2020 - Biologie und Chemie (ab Klasse 10)
Department: Communication & Media Relations
Contact: Dr. Streller, Matthias, Gneist, Nadja
Requirements
- Studium eines naturwissenschaftlichen Faches
- Verbleibende Studiendauer mind. 2 Semester
- Freude an der Vermittlung von Naturwissenschaften und Forschung
- Gute bis sehr gute Noten
Conditions
- 5 - 10 h / Woche an ganzen Wochentagen
- Beginn der Einstellung nach Vereinbarung
Links:
Online application
Please apply online: english / german
Untersuchung des Einflusses von Regularisierungsmethoden auf Bildrekonstruktionsalgorithmen (Id 57)
Student practical training / Bachelor theses / Master theses / Diploma theses
Bei der tomographische Bildrekonstruktion muss ein diskretes inverses Problem gelöst werden, wofür algebraische Methoden wie zum Beispiel ART und CG-Verfahren verwendet werden können. Dabei spielt die Regularisierung, die den Einfluss von Diskretisierungsfehler und Messdatenrauschen auf die Lösung beschränkt, eine entscheidende Rolle. Deren Einfluss auf die Bildrekonstruktion von Röntgen- und Gamma-CT-Messdaten soll untersucht werden. Dazu sind folgende Teilaufgaben zu lösen:
• Implementierung verschiedener Regularisierungsmethoden
• Anwendung der Programme auf Messdaten
• Parameterstudien um die Regularisierungsmethoden für die Messdatensätze zu optimieren.
Department: Experimental Thermal Fluid Dynamics
Contact: Wagner, Michael, Dr. Bieberle, Martina
Requirements
• Programmierkenntnisse in MATLAB
• Grundkenntnisse zur numerischen Behandlung linearer Gleichungssysteme
Links:
