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Associate Engineer - Experimental Nuclear Thermal Hydraulics

Date: Jun 7, 2022

Location: Oak Ridge, TN, US, 37830

Company: Oak Ridge National Laboratory

Requisition Id 8394 


The Energy Systems Development (ESD) Group within the Nuclear Energy and Fuel Cycle Division (NEFCD) at the Oak Ridge National Laboratory (ORNL) is seeking applicants for a Research Associate position. The ESD Group accelerates the design, development and deployment of advanced energy systems such as advanced nuclear reactors, neutron science facilities, energy storage and power conversion systems through experimental research and physical testing.


As a technical staff member in this research and development group, you might contribute to:

  • Development and operation of high-temperature molten salt facilities as proof-of-principal demonstrations of nuclear and solar applications,
  • Surrogate fluid testing of design concepts to validate simulation predictions for system components,
  • Multiphase flow testing to understand dispersed phase behavior and multiphase heat transfer,
  • Characterization of fluid-structure interaction phenomena,
  • Demonstration of advanced construction and/or manufacturing strategies,   
  • Demonstration and integration of advanced measurement methods, including ORNL’s material characterization capabilities.

Work in these areas supports the research programs of the US Department of Energy, partnerships with other federal programs, industry collaborations, and operations at ORNL’s major research facilities, such as the Spallation Neutron Source and High Flux Isotope Reactor. The group operates multiple research laboratories, including a 4500 sq. ft high bay with 1.6 MW of electrical power and 1 MW of chilled water capacity.


Our team members have the opportunity to work collaboratively with diverse subject matter experts from across the laboratory to solve challenging and important problems related to the development, construction, and operation of nuclear energy technologies, other carbon-free energy technologies, and ORNL scientific facilities. ESD staff members are expected to perform work consistent with Environment, Safety, Security, Health, and Quality (ESH&Q) requirements and business rules.  Further, all staff member are expected to support a diverse and inclusive work environment where every employee feels safe, heard, and appreciated—a workplace that sets an example for the broader community.


Major Duties/Responsibilities: 

  • Work with researchers on experiment design, setup, operation, and decommissioning
    • Develop engineering designs for components, systems, and P&IDs
    • Assist with equipment and consumables acquisition: identify specialized equipment and suppliers and place purchase requisitions
    • Support facility construction, instrumentation, and operations
    • Coordinate support (e.g. technicians, craft, calibration services, preventative maintenance, and fabrication engineers) and monitor progress
  • Conduct pre-test analyses to aide experiment design and post-test analyses
    • Use system-level codes, computational fluid dynamics (CFD), and/or finite element analysis (FEA) software to conduct analyses
  • Work in collaboration with the group leader, principal investigator, ES&H staff, and other subject matter experts to support development, documentation and execution of test procedures and associated planning for safety, data security, material handling, etc.  
  • Thoroughly document test setup, experimental results and analysis comparisons


Basic Qualifications:

  • Master’s degree in Nuclear, Mechanical, Aerospace, or Chemical Engineering or closely related field with 1 year of technical experience or   Bachelor’s degree in Nuclear, Mechanical, Aerospace, or Chemical Engineering or closely related field with 3 years of technical experience
  • Physical requirements: Must be able to lift 25 lb unassisted. Capable of standing for extended periods of time, ability to use a ladder, and able to stoop and kneel


Preferred Qualifications:

  • Experience with thermal fluid systems (e.g. hydraulic & pneumatic systems, vacuum systems, high-temperature or high-pressure processes) and programmable logic control (PLC) systems
  • Demonstrated experience in drafting and mechanical design with experience using Solidworks, NX and/or PTC CREO (formerly ProE)
  • Strong written and verbal communication skills
  • Self-motivated and able to multi-task, working on multiple projects simultaneously
  • Experience with the application of CFD, FEA, and/or system-level analysis software (i.e., ANSYS, COMSOL, STAR-CCM+, NX, Dymola, RELAP-3D) to thermal hydraulic test facility or component analysis


About Fusion and Fission Energy and Science Directorate:

The Fusion and Fission Energy and Science Directorate (FFESD) addresses compelling challenges in fission and fusion energy systems, enabling Oak Ridge National Laboratory to pursue national priorities in current and advanced nuclear research, development, and deployment.


FFESD traces its roots to the X-10 Graphite Reactor, the world’s first continuously operated nuclear reactor, and to early innovations in fusion research and engineering. The directorate’s unique facilities, capabilities, and talented scientists and engineers are currently tackling such challenges as extended operations of the current US nuclear reactor fleet; investigating economical and flexible advanced reactor systems; and making fusion energy a viable power source. The directorate leverages synergies between fusion and fission across domestic and international programs.


FFESD leads US ITER, which has the responsibility of designing, fabricating, and delivering hardware for the international ITER fusion project. The directorate also leads the Transformational Challenge Reactor program and the Material Plasma Exposure eXperiment (MPEX), a future world-leading capability that will produce the extreme plasma environments to test materials for use in fusion energy devices. To learn more about FFESD at ORNL go to

Special Requirements:

Physical Requirements: Work involves various physical requirements and working conditions. As such, a pre-hire physical will be required after offer.


Q or L clearance: This position requires the ability to obtain and maintain a clearance from the Department of Energy. As such, this position is a Workplace Substance Abuse (WSAP) testing designated position. WSAP positions require passing a pre-placement drug test and participation in an ongoing random drug testing program.


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.

We accept Word (.doc, .docx), Adobe (unsecured .pdf), Rich Text Format (.rtf), and HTML (.htm, .html) up to 5MB in size. Resumes from third party vendors will not be accepted; these resumes will be deleted and the candidates submitted will not be considered for employment.

If you have trouble applying for a position, please email

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.

Nearest Major Market: Knoxville