Thermal-Hydraulics Engineer (Systems)



Santa Clara, CA, USA
Posted on Thursday, April 27, 2023
Thanks for your interest in Oklo! We are searching for a Thermal-Hydraulics Engineer to join our team.

Position Description

The Thermal-Hydraulics Engineer is responsible for conducting systems-level thermal hydraulic analyses as part of our Reactor Analysis team.

Specific responsibilities may include:
  • Designing, modeling, and analyzing thermal hydraulic systems
  • Developing and conducting systems-level analyses to analyze coupled neutronic and thermal-hydraulic behavior through the reactor system
  • Conducting transient analyses to inform the Reactor Engineering team of system behavior to drive design modifications and improvements
  • Developing and utilizing analysis methods that efficiently and effectively build confidence in a design
  • Performing engineering analyses, which can include thermal, fluid, safety, manufacturability, and cost
  • Collaborating cross-functionally to define design requirements, and providing technical feedback to quick-iterating design teams
  • Coupling systems-level analyses with high fidelity thermal-hydraulic analyses (e.g., CFD)
  • Document work using modern tools and techniques, and write well-written, thoughtful technical reports


We are looking for a Thermal-Hydraulics Engineer that is:
  • Passionate about clean energy
  • Passionate about making advanced fission a reality
  • Willing and able to learn quickly
  • Skilled with tools such as SAS4A/SASSYS-1, SAM, RELAP, TRACE, and GOTHIC
  • Knowledgeable about fast reactor design
  • Experienced with systems-level thermal-hydraulic analysis
  • Eager to work on a dynamic team, receive constructive feedback, and grow with us
  • Willing to think differently and do things in new ways
  • Comfortable in a fast-paced, highly iterative startup environment
  • Excited to think creatively, critically, and reflectively about the problems they are solving, while not leaning only on what has been done before
  • Willing to propose novel and creative solutions to technical problems
  • An excellent writer who can write in modern active voice, so make your cover letter compelling and write it well!
  • Able to communicate technical content and results verbally

Who you are:

A startup person: You aren't driven by titles or hierarchy, and prefer efficiency to excess process. You don't need or expect to have a lot of guidance but you enjoy working in a fast-paced team. If you prefer the culture and feel of a large organization, that is great, but you likely won't enjoy working with us! There is plenty of important work and plenty of good opportunities with organizations like that.

Motivated: You are self-motivated. You bring an enthusiasm to the team, and imbue a sense of passion that goes beyond clocking in and clocking out. This isn't about a fake or arbitrary "pieces of flair" mentality or lack of work-life balance! It is about being a part of the vision and feeling a part of reaching team goals.

A team-player: Oklo genuinely is a team. We aren't about taking credit for ourselves, and we aren't about pushing blame to others. We do incredible things because we work as a team.

An excellent communicator: We need a person who is not only technically competent but also a clear and upbeat communicator.

Creative: Being creative means that when things fall outside clear scopes or processes or problems arise without clear solutions, you are able to identify it as well as invent ways to solve a problem or fill a need without micromanagement. The successful person in this job will not only be creative, but also enjoy being creative and solving open-ended problems which may change day-by-day.

Detail-oriented: This focus is a big part of excellence, consistency, and quality. Excellent grammar and spelling matter for both good communication as well as the image of the company that we put forward.

Minimum Qualifications:
  • Proficiency with thermal-hydraulics analysis
  • Bachelors, Masters, or PhD in a technical field, such as nuclear, mechanical, or aerospace engineering
  • Experience with systems-level analysis codes such as SAS4A/SASSYS-1, SAM, RELAP, TRACE, GOTHIC, or equivalent is highly recommended
  • Experience with reactor transient analysis methods
  • Experience with data processing (e.g., pre-processing, post-processing, scripting) is highly recommended
  • Fluency with Python
  • Experience with CI/CD computing environments

Bonus Qualifications:
  • Experience with nuclear engineering principles and multi-physics analysis methods for engineering applications, particularly as they relate to advanced reactors
  • Competency with modern software engineering practices and programming languages
  • Core competencies in heat transfer, fluid dynamics, and thermodynamics first principles

About Oklo compensation:

Salary: $73,000-$157,000

Salary may fall outside of the range provided and will be dependent on applicant experience.

Oklo offers flexible time off, equity, competitive pay, 401k, health insurance, FSA, flexible work hours, and other benefits.

We are looking to fill this position immediately!

About Oklo Inc.: Oklo is a California-based company developing clean energy plants to provide emission-free, reliable, and affordable energy using advanced fission. Oklo is a fast-growing startup with a history of reliable funding and milestones for more than 5 years. Oklo's first product is a microgrid scale powerhouse. The powerhouse can produce clean energy for decades without needing to refuel, and also has the capability to turn nuclear waste into clean energy.

Oklo received a Site Use Permit from the U.S Department of Energy, demonstrated fabrication of its fuel, was awarded fuel from the Idaho National Laboratory, and submitted the first accepted advanced fission license application to the regulator.

Oklo has been featured in Popular Mechanics, Wired, Architectural Digest, Hyperallergic, POWER Magazine, has been the subject of a Harvard Business School case, and was featured in the documentary The New Fire, among many other features.