Nuclear Thermal Hydraulics Strategic Hire

Oak Ridge National Laboratory - Oak Ridge, TN (30+ days ago)4.4


The Advanced Reactor Engineering (ARE) Group within the Reactor and Nuclear Systems Division (RNSD), Nuclear Science and Engineering Directorate, Oak Ridge National Laboratory (ORNL), seeks an outstanding, highly-motivated professional with interests in developing, demonstrating and qualifying predictive simulation software for nuclear thermal hydraulics and safety applications. We seek to develop an international leadership position at the intersection of high-performance computational fluid dynamics (CFD), reduced order thermal hydraulic models and advanced data analytics.

RNSD conducts leading-edge science, technology, and engineering research and development (R&D) for current and advanced nuclear reactors and fuel cycles; storage, transport, and disposal of used nuclear fuel; non-reactor nuclear systems (e.g., accelerators, irradiation facilities, fusion energy systems); and nuclear security and defense programs.

The Advanced Reactor Engineering Group delivers outstanding solutions to challenging fluid, heat transfer and irradiation engineering problems through a unique integration of design, simulation, fabrication and experimentation expertise. ARE develops and deploys advanced thermal/fluid analysis and multi-physics simulation technologies to support nuclear reactor design and safety evaluations. These technologies include high resolution direct numerical simulation and large eddy simulation methods, Reynolds Averaged Navier Stokes (RANS) methods, coarse grid distributed resistance and empirical sub-channel methods, and lumped parameter system analysis methods. The group contributes to the development of multiphysics virtual reactor simulation capabilities and leverages ORNL’s world leading high performance computing (HPC) platforms for nuclear and non-nuclear applications. Ongoing research in the group supports a variety of customers within the US Department of Energy, the Nuclear Regulatory Commission, and other government and private organizations.

The ARE group is a core contributor to a larger ORNL CFD community of practice. The community of practice unites approximately 50 users and developers who represent 13 of 20 technical divisions from all five technical directorates. Participants hold regular meetings to support technical exchange, develop joint proposals and advocate for internal support of CFD applications, tools and infrastructure. The community develops, qualifies and applies a variety of CFD codes for high performance computing platforms to a wide range of engineering problems.

The ARE group also manages three major experimental laboratories with state of the art instrumentation, works with diverse coolants including molten salts and liquid metals, and conducts experiments and analysis to support for ORNL’s Spallation Neutron Source, High Flux Isotope Reactor, molten salt reactor development, concentrated solar power development and other energy applications.

Major Duties / Responsibilities

The successful candidate will be responsible for developing new thermal hydraulics R&D programs and identifying research directions to enable effective integration of the existing research teams and portfolios. He/she will work with a variety of experienced thermal hydraulic engineers to develop advanced thermal hydraulic methods and apply ORNL’s HPC resources to help resolve problems of national importance. The candidate will also lead efforts to align existing thermal hydraulic programs and define future paths for thermal hydraulic development and analysis in the ARE group of the Reactor and Nuclear Systems Division.

One initial focus for the position will be to define a roadmap to enhance or replace conventional thermal hydraulic approaches to solve the most challenging thermal/fluid problems in advanced nuclear reactor technology. High fidelity analyses of most reactor and nuclear systems require that simulations account for a wide range of length and time scales and are scalable to a large number of computing processors. Consequently, development of CFD-informed multi-scale solutions, direct integration of large data sets, and integration/acceleration using reduced order models will be the key elements for this position. The successful candidate will capitalize on his/her strong history of successful innovation in numerical methods and parallel software development to identify and implement state-of-the-art solutions to the most complex thermal/fluid problems.

The candidate will be responsible for interfacing with personnel from various technical disciplines including reactor physics, structural analysis, fuel performance/ mechanics, chemistry, scientific computing, and advanced data analytics to enable integrated multi-physics analysis. The position provides the opportunity to collaborate with world-class expertise in these technical areas, including the support of extensive experimental facilities and experimental personnel. He/she will work in a team environment, interacting with and guiding ORNL staff, both within and outside the TH&IE group. The candidate will be expected to propose, lead, and encourage publication of thermal-hydraulic R&D activities.

Qualifications Required

Candidates must have a PhD degree with 6 or more years of experience in nuclear, mechanical, or chemical engineering or engineering physics. Experience must exhibit strong focus on development of CFD codes and/or reduced order thermal hydraulics codes to solve complex high-consequence problems and emphasize development of software for low Mach number internal flows, multi-phase flows with phase change, and conjugate heat transfer in large domains with complex geometries. The candidate is expected to have sufficient background to facilitate direct application of developed methods and software to nuclear science and technology problems.

Candidates must have skills necessary to form and lead teams that develop the advanced thermal/fluid methodologies needed to perform nuclear design and safety calculations and be able to effectively interface with project sponsors and laboratory management.

Excellent verbal, presentation, and writing skills are required to enable effective interaction with peers, program managers, and sponsors. Additionally, this position requires that the candidate work with other personnel throughout the Laboratory to develop new programs, originate and/or contribute to proposals, and pursue new funding opportunities.

Qualifications Desired

The ideal candidate will have a PhD degree with 10 or more years of experience in nuclear, mechanical, or chemical engineering or engineering physics. Experience in the development of multiphase, especially boiling and flashing, simulation capabilities is desired. The ideal candidate should have documented experience working on large-scale, parallel computational platforms is highly desirable. Proficiency in common scientific programming languages is desired, such as C, C++ or Fortran90/95 and parallel programming paradigms, as well as HPC middleware and languages such as OpenMP, MPI, CUDA or OpenCL.

She/he should have demonstrated skills leading and working in a team environment, spearheading new R&D initiatives, and be motivated to innovate and think ‘out of the box’ to solve a variety of challenging engineering problems. She/he should have skills necessary to effectively interface with project sponsors, external collaborators and laboratory management.

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Job Type: Full-time