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Postdoctoral Research Associate ─ Computational Fluid Dynamics (CFD)

Date: Mar 18, 2023

Location: Oak Ridge, TN, US, 37830

Company: Oak Ridge National Laboratory

Requisition Id 10164 


Oak Ridge National Laboratory is the largest US Department of Energy science and energy laboratory, conducting basic and applied research to deliver transformative solutions to compelling problems in energy and security.


The Advanced Reactor Engineering and Development (ARED) Section in the Nuclear Energy and Fuel Cycle Division (NEFCD) of Oak Ridge National Laboratory (ORNL) is seeking a Postdoctoral Research Associate to support the development, qualification, and deployment of Computational Fluid Dynamics (CFD) simulation codes, methods, and best practices for thermal-hydraulics analyses of energy systems. 


This position will be part of the Thermal Hydraulics group, which supports the development and application of multiphysics and multiscale models and simulations supporting the design, optimization, qualification, and deployment of thermal management systems associated with a broad range of large-scale energy production and energy-intensive industrial applications.   



Major Duties/Responsibilities: 

  • Work with experienced staff to develop next-generation CFD and thermal-hydraulics methods and models for a variety of nuclear reactor, or thermal energy systems, using world-leading high-performance computing platforms
  • Perform large-scale multiphase Reynolds Averaged Navier Stokes (RANS) simulations of reactor cores, heat exchangers, pumps, pressurizers, and condensers
  • Support integrated multi-physics simulations of reactor core, and other system components
  • Develop reduced-order calibration approaches and apply machine learning and Bayesian calibration methods to enable multi-scale, multi-physics model development
  • Complete simulation verification, model validation, uncertainty quantification, and documentation
  • Optimize system and component designs for performance and safety


Basic Qualifications:

  • A PhD in in nuclear, mechanical, or chemical engineering or engineering physics or a related field completed within the last 5 years


Preferred Qualifications:

  • Demonstrated experience in applying and extending CFD codes for application to nuclear, or similarly complex, thermal energy systems
  • Experience with commercial CFD codes such as STAR-CCM+, ANSYS Workbench or COMSOL Multiphysics, open-source CFD codes such as OpenFOAM or Nek5000, optimization and generative design tools such as HEEDS, and/or the Dakota or RAVEN uncertainty quantification tools
  • Background in FORTRAN, C, and/or C++ applied programming and knowledge of Python, Java, or other scripting languages
  • Experience using parallel Linux computing platforms, parallel job submission scripts, common software repository tools, and parallel visualization software
  • Excellent written and oral communication skills
  • Motivated self-starter with the ability to work independently and to participate creatively in collaborative teams across the laboratory 
  • Ability to function well in a fast-paced research environment, set priorities to accomplish multiple tasks within deadlines, and adapt to ever changing needs


Applicants cannot have received their Ph.D. more than five years prior to the date of application and must complete all degree requirements before starting their appointment. The appointment length will be for up to 24 months with the potential for extension. Initial appointments and extensions are subject to performance and the availability of funding.


Moving can be overwhelming and expensive. UT-Battelle offers a generous relocation package to ease the transition process. Domestic and international relocation assistance is available for certain positions. If invited to interview, be sure to ask your Recruiter (Talent Acquisition Partner) for details.

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This position will remain open for a minimum of 5 days after which it will close when a qualified candidate is identified and/or hired.

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ORNL is an equal opportunity employer. All qualified applicants, including individuals with disabilities and protected veterans, are encouraged to apply.  UT-Battelle is an E-Verify employer.

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