Category Archives: jobs - Page 4

PhD in numerical fluid mechanics on the transition to turbulence in flows with liquid and solid phases, application to the optimization of flowrate measurements in oil pipes. NEL/COVENTRY UNIVERSITY (UK)

Applications are invited to apply for a 4-year PhD studentship in experimental fluid mechanics at the Applied Mathematics Research Centre, Coventry University (http://www.complexity-coventry.org/home/). The project is funded by the National Engineering Laboratory, who provides calibration services for flowmeters used in offshore oil extraction plants (www.tuvnel.com). Precisely measuring the quantity of oil extracted from wells is a major economical challenge for the oil industry. Current flowmeters rely on assumptions on the flow profile in pipelines, which are being challenged both by the multiphase nature of the flow and its transitional character. To measure flow rates more precisely, it is now necessary to characterize flow regimes in real time, and this demands a precise understanding of the transition between laminar and turbulent states in multiphase pipe flows.

Pipe flow is a classical problem in fluid dynamics. Its simplicity of form and importance to industry and engineering has invited research for well over 100 years. In the case of a single phase the problem is relatively well understood in terms of transient turbulence. Patches of turbulence can be observed once the nondimensional flow rate (Reynolds number) exceeds 2000. As the flow rate is increased, turbulence becomes easier to initiate and turbulent patches start to spread along the pipe. With the addition of solid particles to the flow, the picture becomes less clear. Despite the great importance of particulate flow to a range of real world problems from chemical engineering to food processing, our understanding of how solid-liquid multiphase flow behaves is relatively poor. In the case of fully developed turbulence, work has been done on the impact of particle size on turbulence intensity and particle distribution. Somewhat less has been done on the problem of intermittent turbulence, and turbulence transition. These questions need to be answered to be able to determine flow rate precisely from the signals delivered by standard flowmeters.

The doctoral student will be in charge of the numerical part of this work. Transitional particulate channel flow has previously been investigated, but only in the case of the small periodic boxes. That literature will inform the beginnings of this project as we seek to employ similar methods in initially periodic pipe flow before moving to non-periodic flow. Cutting edge ideas (exact solution finding, nonlinear transient growth, etc) from the classical transition problem will be applied to this new field. The work will be compared extensively to experimental work to validate the approach taken and the results will be used to obtain more precise measurements from current and future flowmeters.

This challenging problem offers a rare opportunity for high-profile fundamental research in fluid mechanics (typically expected to generate publications in leading journal such as Journal of Fluid Mechanics) with, at the same time, a direct application to a concrete industrial need.

Successful candidates are expected to hold a MSc or equivalent in fluid mechanics or a related discipline (Physics/ Engineering/ Mathematics) and experience of numerical coding. Abilities in this field will have been demonstrated at MSc level.  The student will receive a tax-free bursary in excess of approx. £13.5k per annum (approx £17kEuros). Please note that this position is available to EU citizens only. The position will be open until a suitable candidate is found.

To apply, please forward a CV and academic records to Chris Pringle (chris.pringle(at)coventry.ac.uk) or Alban Pothérat (alban.potherat(at)coventry.ac.uk). Informal enquiries are welcome. The position will remain open until a suitable candidate is found.

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Alban Potherat
Coventry University
Applied Mathematics Research Centre

Two Ph.D. Positions at Coventry University, Applied Mathematics Research Centre

PhD in experimental fluid mechanics on the transition to turbulence in flows with liquid and solid phases, application to the optimization of flowrate measurements in oil pipes. NEL/COVENTRY UNIVERSITY (UK)

Applications are invited to apply for a 4-year PhD studentship in experimental fluid mechanics at the Applied Mathematics Research Centre, Coventry University (http://www.complexity-coventry.org/home/). The project is funded by the National Engineering Laboratory, who provides calibration services for flowmeters used in offshore oil extraction plants (www.tuvnel.com). Precisely measuring the quantity of oil extracted from wells is a major economical challenge for the oil industry. Current flowmeters rely on assumptions on the flow profile in pipelines, which are being challenged both by the multiphase nature of the flow and its transitional character. To measure flow rates more precisely, it is now necessary to characterize flow regimes in real time, and this demands a precise understanding of the transition between laminar and turbulent states in multiphase pipe flows.
Pipe flow is a classical problem in fluid dynamics. Its simplicity of form and importance to industry and engineering has invited research for well over 100 years. In the case of a single phase the problem is relatively well understood in terms of transient turbulence. Patches of turbulence can be observed once the nondimensional flow rate (Reynolds number) exceeds 2000. As the flow rate is increased, turbulence becomes easier to initiate and turbulent patches start to spread along the pipe. With the addition of solid particles to the flow, the picture becomes less clear. Despite the great importance of particulate flow to a range of real world problems from chemical engineering to food processing, our understanding of how solid-liquid multiphase flow behaves is relatively poor. In the case of fully developed turbulence, work has been done on the impact of particle size on turbulence intensity and particle distribution. Somewhat less has been done on the problem of intermittent turbulence, and turbulence transition. These questions need to be answered to be able to determine flow rate precisely from the signals delivered by standard flowmeters.

The doctoral student will be in charge of the experimental part of this work, which will consist in setting up a two-phase flow loop in Coventry, where the flow will be mapped by Particle Image Velocimetry. The aims are to identify flow patterns in transitional regimes, understand their dynamics and also use this knowledge to obtain more precise measurements from current and future flowmeters. In the later stage of the project, experiments will be conducted on a larger scale at NEL (Glasgow), on one of the largest testing rigs of this type in the world. The student will work within a team of 5 scientists and engineers overseeing the theoretical and experimental parts of the projects and will benefit from technical support specialised in the construction of fluid mechanics experiments.
This challenging problem offers a rare opportunity for high-profile fundamental research in fluid mechanics (typically expected to generate publications in leading journal such as Journal of Fluid Mechanics) with, at the same time, a direct application to a concrete industrial need. Furthermore, NEL is prepared to offer a position to the student upon completion of a PhD deemed of sufficiently high standard.

Successful candidates are expected to hold a MSc or equivalent in fluid mechanics or a related discipline (Physics/ Engineering/ Mathematics) and have a pronounced taste for experimental fluid mechanics. Abilities in this field will have been demonstrated at MSc level. The student will receive a tax-free bursary in excess of £13.5k per annum (approx £17kEuros). Please note that this position is available to EU citizens only.
To apply, please forward a CV and academic records to Alban Pothérat (Coventry University, alban.potherat(at)coventry.ac.uk). Informal enquiries are welcome. The position will be open until a suitable candidate is found.

Alban Potherat
Coventry University
Applied Mathematics Research Centre

Open Position at Princeton Plasma Physics Laboratory

The Princeton Plasma Physics Laboratory seeks to fill an associate research physicist position at Laboratory Astrophysics Division in Plasma Science & Technology Department. Under supervisions by senior personnel, the researcher will perform campaigns in liquid metal Magnetorotational Instability experiment to investigate mechanisms for fast angular momentum transport, and also the nonlinear physics of Rossby waves and zonal flow system. Candidates must have an extensive background in experimental physics, preferably fluid dynamics, liquid metal MHD and plasma physics. The major responsibilities include handling liquid gallium in laboratory, designing and implementing diagnostics, performing experiments, analyzing data, interpreting, presenting and publishing results jointly with other researchers. Coordinating activity with other technical, engineering and administrative personnel is also essential. Development of new ideas should help grow the area of laboratory plasma astrophysics at PPPL in the long term. Applicant should have a Ph.D. in plasma physics or related physics, with preference given to applicants with experience in fluid dynamics, liquid metal MHD and its diagnostics, data acquisition, data processing, and applications to astrophysics and geophysics.

You can use my contact info below.

Thanks,
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Hantao Ji
Professor of Astrophysical Sciences, Princeton University
Distinguished Research Fellow, Princeton Plasma Physics Laboratory
Homepage: http://w3.pppl.gov/~hji; Phone: (609)243-2162

POSTDOC POSITION AT TU ILMENAU

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(from Christian Karcher, Ilmenau, Germany)

The Research Training Group (RTG) on Lorentz Force Velocimetry and Lorentz Force Eddy Current Testing at Ilmenau University of Technology offers

1 full-time postdoctoral position
in theoretical and computational magnetohydrodynamics.

The RTG is sponsored by the Deutsche Forschungsgemeinschaft DFG. Final funding approval for this position is expected 08 May 2014. The position is thus available as of 01 June 2014. The position lasts two years. Extension up to a total of 4½ years is possible. The position is paid according to TVL E14 scale (approx. 45.000 – 55.000 EUR per year before tax). It is strictly dedicated to promote and qualify women in science.

The measurement of flow velocities in hot and aggressive liquids like metal melts and molten glass is a grand challenge in industrial fluid mechanics. A physically closely related challenge is the detection of deeply lying flaws and inhomogeneities in electrically conducting solid materials. Since 2004, scientists at Ilmenau University of Technology have been developing two novel technologies termed Lorentz force velocimetry and Lorentz force eddy current testing to meet these challenges. Both technologies are based on measuring the Lorentz forces that are induced by the interaction of electrically conducting moving substances and magnetic fields.

Within the RTG, the basic physics of these technologies shall be explored by performing high-precision model experiments, high-resolution numerical simulations, and intense analytical modeling. The RTG provides a creative and inspiring environment, excellent laboratory facilities, state-of-the-art scientific computing facilities, and the possibility of collaborating with industry and with foreign institutions. Further details can be found at www.tu-ilmenau.de/lorentz-force.

Successful candidates for the position should have

• an excellent doctoral degree, preferably in engineering, physics, or applied mathematics,
• an excellent knowledge of the English language,
• a high motivation for interdisciplinary work in an international scientific team,
• a strong background in modeling of multi-physics problems.

Experience in theoretical and computational magnetohydrodynamics is desirable but not required.

Handicapped applicants with identical qualification will be considered with priority. Special services are available concerning social matters.

Applicants should e-mail the complete set of documents (see www.tu-ilmenau.de/lorentz-force) in PDF format as soon as possible but not later than 30 April 2014 to lorentz-force(at)tu-ilmenau.de.

Preliminary information is given by the RTG Head, Professor Jörg Schumacher and the RTG Scientific Coordinator, Dr. Christian Karcher, who can be contacted electronically under joerg.schumacher(at)tu-ilmenau.de and christian.karcher(at)tu-ilmenau.de, respectively.

New position in Experimental MHD/Heat & Mass Transfer at UCLA

(from Sergey Smolentsev, USA)

The Fusion Science and Technology Center at University of California, Los Angeles invites applicants for a research position in Experimental MHD / Heat & Mass transfer. The studies are related to liquid metal MHD flows in closed ducts in conditions relevant to a fusion reactor blanket. Successful candidates are expected to have experience/background in the area of experimental fluid dynamics/heat & mass transfer. Experience in experimental studies of liquid metals (PbLi, InGaSn, NaK, Hg), especially in the presence of a strong magnetic field, and working knowledge of liquid-metal flow diagnostics, such as ultrasound velocimetry and potential probes, is desirable. Considerations will be given to both recent university graduates (Ph.D. is required) and senior scientists with a multi-year experience in the field.

The position is available starting from September 01, 2013. Applications or questions about the position should be sent to Sergey Smolentsev (sergey(at)fusion.ucla.edu) and copy to Mohamed Abdou (abdou(at)fusion.ucla.edu).

New Positions for PhDs and PostDocs at HZDR

  1. The Helmholtz Centre Dresden-Rossendorf (HZDR) invites for applications concerning a PhD position within a project devoted to the further development of the Contactless Inductive Flow Tomography (CIFT) for flow measurements in electrically conducting flows. The availability of appropriate measurement techniques is a necessity for any experimental work on liquid metal technologies. Exposing the flow of liquid metals like steel or silicon to an externally applied magnetic field, electrical currents are induced which give rise to a perturbation of the applied field. This flow induced field perturbation, which is detectable outside the fluid volume, contains information about the flow structure and can be exploited to reconstruct the velocity field. Previous tests at laboratory scale revealed a great potential of the CIFT method for the online monitoring of flow structures in real industrial processes.Applicants must have a master degree in physics, electrical engineering or fluid engineering.
  2. The Helmholtz Centre Dresden-Rossendorf (HZDR) invites for applications concerning a PhD position within a project devoted to experimental investigations with respect to the behaviour of gas bubbles and bubble swarms in liquid metal flows. Many technical applications in power engineering, metallurgy and casting rely on liquid metal two-phase flows. In metallurgy, gas injection is routinely applied at various stages to promote chemical reactions and to stir the melt for reducing temperature and/or concentration gradients together with promoting an effective removal of impurities. On the other hand, gas entrainment into liquid metal coolants is an essential safety issue in the design of liquid metal cooled fast reactors. Visualizations of liquid metal two-phase flows can be obtained by means of X-ray radioscopy. The formation, the coalescence and breakup of gas bubbles will be observed in low melting point alloys. The method delivers data about the size, the velocity and the trajectory of the bubbles. This information will be used by another partners in the project to develop advanced models of bubble coalescence and breakup for liquid metals.Applicants must have a master degree in physics, electrical engineering or fluid engineering.
  3. The Helmholtz Centre Dresden-Rossendorf (HZDR) invites for applications concerning a postdoc position within a project devoted to the development of casting technologies ODS steels. Oxide dispersion strengthening (ODS) of high-Cr steels is a promising way to get materials for high-temperature applications. The mechanical and corrosive properties are significantly improved compared to present-day steels. However, it is difficult to disperse ceramic particles uniformly in liquid metals because of their poor wettability and their large surface-to-volume ratio, which easily induces agglomeration and clustering. In case of nano-dispersed aluminum alloys the homogeneous distribution of nano-particles has been obtained by ultrasonic vibration of the melt. This project focuses on the problem whether alternating electromagnetic forces can be designed in such a way that an intense vibration of the melt can be achieved, similar to the case of ultrasonic vibration. The possibility of creating electromagnetically induced pressure waves in a metal melt shall be investigated.Applicants must have a PhD in physics or engineering with a strong background in material science, fluid mechanics or magnetohydrodynamics.All position are available from June 1, 2013 until May 31, 2016. A prolongation until October 2017 is conceivable.

Applications should be sent to Sven Eckert (s.eckert(at)hzdr.de) or Gunter Gerbeth (g.gerbeth(at)hzdr.de) before May 31st.

Many thanks and best regards
Sven

Sven Eckert
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Helmholtz-Zentrum Dresden-Rossendorf (HZDR)
Institute of Fluid Dynamics
Head of the Department Magnetohydrodynamics
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Contact:
Bautzner Landstraße 400, 01328 Dresden
P.O. Box: 510119, 01314 Dresden
Tel. +49 351 260-2132 (Office)
Fax: +49 351 260 1 2007
s.eckert(at)hzdr.de

LECTURER/SENIOR LECTURER IN FLUID MECHANICS at Coventry University

LECTURER/SENIOR LECTURER IN FLUID MECHANICS

Salary per annum : £29,344-£37,346 (L)/£35,247-£50,187(SL)

The Fluid Dynamics Group within the Applied Mathematics Research Centre at Coventry University is seeking to appoint a Lecturer/Senior lecturer in fluid mechanics to support its growing activities in the fields of geophysical fluid dynamics and turbulence.

The Group currently comprises 7 Staff and PhD students and runs projects combining theory, numerical simulations and experiments, supported by a number of grants from research funding bodies and international partnerships. It has priority access to extensive on-site high performance computing provisions and runs two major experimental facilities: a magnetohydrodynamics lab, which includes a large bore, purpose-built 8T superconducting magnet, as well as a modular experimental platform for the study of turbulence in liquid metals, in collaboration with the French CNRS in Grenoble.

The successful candidate will be expected to primarily focus on research, and will benefit from a reduced teaching load for this purpose. He/she will help to develop existing themes in geophysical fluid dynamics and turbulence, and to extend the group’s existing long-term international collaborations (with the CNRS amongst others). At the same time, the appointee will be encouraged to start new directions of research, within the wide remit of fundamental and applied Fluid Dynamics.

Research activity will involve leading and co-leading projects both theoretical/numerical and experimental in nature, supervising PhD students and post doctoral researchers, and actively seeking funding, from national and international funding agencies, or from private funders.

The smaller teaching role will involve helping to develop and teach courses at Master level in Applied Mathematics/Physics, as well as some undergraduate teaching.
Candidates should hold a PhD or equivalent in any area of fluid mechanics/physics and have an established track record of publishing their work in the best international journals in the discipline. Evidence of previous commitment to attract research funding from major agencies or private funders will be an advantage.
The post will be for an initial period of four year and will be made permanent on satisfactory performance.

Informal inquiries are encouraged, please contact Professor Alban Potherat (alban.potherat(at)coventry.ac.uk, +44(0)2477 65 88 65 (email only from April)),

Application deadline 20/04/2013
Application must be made online at
https://staffrecruitment.coventry.ac.uk/tlive_webrecruitment/wrd/run/ETREC105GF.open?WVID=1861420Izv

PhD studentship at Ecole Polytechnique, FR: Electromagnetically-launched strong shocks relevant for accretion shocks in astrophysics

Length: 3 year studentship
Funded by: Plas@Par excellence laboratory – University Pierre & Marie Curie, Paris
Maintenance grant: €1,700 per month (http://plasapar.upmc.fr/?page_id=544)
Supervised by: Dr Jean Larour, Dr Chantal Stehlé
The proposed enrolment date is 1st October 2013
The deadline for application is 15th May 2013.

Details of proposed research

Strong shocks are present in astrophysics, from stellar infancy (matter accretion from stellar disk to the young star, ejection in plasma jets) to supernovae explosion. Topology and dynamics are complex: roles of radiation, NLTE cooling or B-field. It is crucial to study such hypersonic shocks (Mach number>20) in the laboratory and to compare with simulation. So far, studies are done on large lasers, addressing pure hydro-radiative shocks (50-150km/s, 0.1-1bar). The project extends the class of shocks in radiative regime, at lower velocities, using a flexible and repetitive setup.

The PhD student will first perform experiments on a versatile kJ-class generator launching quasi-planar shocks up to 20km/s in low density gas. The setup is currently upgraded to get higher velocities, allowing to study various regimes of shock waves, depending on the gas, pressure and external B-field. The main task will be to design, to implement and to exploit a comprehensive suite of diagnostics of the shock plasma, the data being used to build a model and to benchmark 2-D or 3-D codes. These shocks will be used to prepare new diagnostics in view of foreseen experiments on laser-driven shocks.

Successful applicants must hold a Master of science in engineering, physics, astrophysics or equivalent. A previous experimental experience, in data acquisition or computer simulation is a merit, as a high evel in french or english. Please send your CVs to Dr Jean Larour (jean.larour(at)lpp.polytechnique.fr) and Chantal Stehlé (chantal.stehle(at)obspm.fr)

PDF version: PhD studentship at Ecole Polytechnique


Jean LAROUR
Laboratoire de Physique des Plasmas LPP
Ecole polytechnique 91128 Palaiseau
tel 33(0)169 33 59 54 fax 33(0169 33 59 06
jean.larour(at)lpp.polytechnique.fr
http://www.lpp.fr

Research Engineer/Project Manager Position at Georgia Tech, USA

One research engineer/project manager position is available starting from February 2013 in the Atomistic Simulation & Energy (A.S.E.) research group at Georgia Tech. The primary function for this position is to lead the construction and testing of two lab scale prototype high temperature liquid metal loops for a concentrated solar application. One liquid metal loop will be tested in a solar simulator, while the second test loop will involve thermochemical reactors designed for water splitting/hydrogen production. The idea (see Fig. 1 on page 2) is to capture highly concentrated sunlight (> 5 MW/m2) at high temperature > 1300°C in the sensible heat of a liquid metal heat transfer fluid (i.e. tin). The sensible heat can be later used for direct power generation or thermochemical fuel production (water splitting) as a new route to clean, renewable and dispatchable utility scale electricity generation.

More details here: Open Positions – Research Engineer

Please send a CV, representative publications, a short one paragraph description of career goals and why you’re interested in this project, as well as contact information for three references to Asegun Henry (ase(at)gatech.edu). Review of applications will start immediately and will continue until the position is filled.

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Asegun Henry, Ph. D.
Woodruff School of Mechanical Engineering
Georgia Institute of Technology
495 Tech Way, CNES Bldg, Rm 223
Atlanta, GA 30332
Office Phone: 404-894-7514
ase(at)gatech.edu
http://www.me.gatech.edu/faculty/henry-a