Senior Thermal Modeling Engineer (CFD)

Radiant is an El-Segundo, CA-based clean energy startup building a nuclear microreactor. A climate-friendly alternative to diesel generators, Radiant's Kaleidos 1MW microreactor will be the world's first portable, zero-emissions power source that works anywhere. We plan to test our development reactor by 2026 and if successful, it will be the first new commercial reactor design to achieve a fueled test in over 50 years. Radiant's goal is to bring one of the world's first factory-constructed microreactors to market. Our microreactor can bring power to remote parts of the world and provide backup power for life-saving applications in hospitals or disaster-relief scenarios. 

Senior Thermal Modeling Engineer (CFD)

Radiant is seeking a driven Senior Thermal Modeling Engineer with expertise in CFD and thermal FEA modeling. You will design, develop and implement simulations for the Kaleidos microreactor to ensure high fidelity, reliability, and safety of our systems. You’ll work on cutting edge technical problems for a high temperature gas reactor that inform decisions across reactor systems, cooling systems, shielding, and more. You will have an opportunity to work in an interdisciplinary environment and drive milestones forward to unlock commercialization of the first mass-produced nuclear reactor.

Responsibilities and Duties:  

• Develop and enact thermal analysis plans for Kaleidos.


• Breakdown complex analysis requests asks into manageable simulations.


• Translate high-fidelity CAD into simplified geometry for analysis.


• Develop thermal to structural analysis pipeline.


• Document analysis results into simple and actionable outputs.


• Verify validity of results via simplified methods (hand calculations / spreadsheet calculations)

Required Qualifications and Skills: 

• Bachelor’s degree in engineering, physics, or similar field from an accredited institution.  


• 4+ years of experience with Star CCM+ or Ansys Fluent. 


• Expertise in finite element and computational fluid dynamics modeling methods.


• Knowledge of underlying mathematical principles behind thermal FEA and CFD (finite methods, transport physics, turbulence models, etc.).

Desired Qualifications and Skills:  

• Proficiency with CAD software (Siemens NX).


• Knowledge of nuclear physics principles.


• Experience with radiation heat transport modeling.


• Experience communicating and distilling information with cross-functional teams. 


• Driven, self-motivated, and takes ownership of work end to end.

Additional Requirements

• Must be willing to work extended hours and weekends as necessary to accomplish our mission.


• Must work 100% onsite at El Segundo HQ.

Employee Benefits for Eligible Employees:

• Stock: Substantial incentive stock plan for all full time, salaried employees.


• Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.


• One Medical: Sponsored memberships for employees and their dependents. 


• Vision: 100% top tier plan coverage + 50% for dependents.


• Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.


• Voluntary Life, Accident, Hospital, Critical Illness, Commuter and FSA are offered as employee contributed benefits.


• Free snacks and drinks onsite. 


• Flexible PTO policy.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time. This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.