Thermal Hydraulics Intern

This is a Full-time 16-month role commencing May 2026

For this role in Oakville, Ontario, The hourly wage range for this position is CAD $25 to $35 per hour. The actual wage offered will be determined based on factors such as education, experience, knowledge, skills, abilities, applicable market data for the work location, and internal equity considerations.

Come join us at Terrestrial Energy, a US developer of advanced, Generation IV nuclear reactors. We are growing our workforce to develop and deploy our Integral Molten Salt Reactor (IMSR) small modular nuclear plant to provide cost-competitive, clean firm heat and power to industry.

The Company has recently completed a merger creating a publicly listed operating company (NASDAQ “IMSR”), to secure the capital resources for our next growth phase. With the current alignment of US Federal and State government, as well as industry interest in Small Modular Reactor (SMR) and advanced reactor technologies such as Terrestrial Energy’s IMSR, there is today a unique and compelling opportunity to participate in the execution of the company’s growth business plan.

The Company is building a team of high-performing business professionals and leaders in engineering, R&D, product management and business development areas at our Charlotte, North Carolina headquarters and future project sites. We are looking for talented individuals who can help build the organization, processes, and goal-orientated corporate culture to lead the company in our expansion. We are seeking people who:

• Have US market experience and perspectives bringing good judgement and innovative approaches to problem solving and business plan execution.
• Have demonstrated exceptional performance in past engineering projects.
• Offer exceptional leadership and team building capabilities.
• Have a deep understanding of the requirements for advanced reactor development.
• Can assist in the creation of the discipline and organized company structure, and contributed to a culture of excellence, necessary for the development and deployment of the Company’s IMSR plant.
• Can thrive in a fast growing and opportunity business environment, and are capable of flexibility and adaptability at a time of organizational change.
• Have the specific skillset and experience for the following role:

The Thermal Hydraulics Intern, under the direction of the Thermal Hydraulics manager, is primarily responsible for the design and analysis of the fundamental heat transfer systems of the company reactor technology and supporting licensing activities. The successful candidate will perform fundamental analyses of heat generation and fluid flow within the reactor core and supporting heat transfer systems, through calculations and software modelling, contributing to the various operating states of the company reactor technology as well as safety analyses of advanced molten salt reactor design.

• Develop thermal hydraulic models in system level thermal hydraulic codes such as Flownex and GOTHIC
• Perform steady state and transient simulations, sensitivity analysis, and optimization studies to improve designs
• Perform hand calculations and employ software for basic thermal hydraulic systems such as heat and mass balances and heat exchangers
• Develop code in various programming languages to support simulations
• Perform code-to-code validation with CFD models

• Prepare simulation results reports, assessment reports and design documents
• Create clear visualizations and presentations of simulation results to peers and management to support decision making
• Review research on existing methodologies and operation experience related to nuclear engineering and molten salt applications

• Work closely with members of the Thermal hydraulic team, as well as cross-collaboration with the R&D, Physics, Safety, and Mechanical disciplines
• Support design by participating in design reviews and technical meetings
• Interface with external partners including national laboratories

• Thermodynamics and Heat Transfer
• Fluid Dynamics
• Simulation experience
• Power plant engineering
• Communication
• Critical Thinking
• Decision Making
• Problem Solving
• Results Orientation
• Team player with the ability to collaborate and interact with other groups
• Flexible and adaptable to change

• Actively working towards an undergraduate or graduate degree in mechanical, chemical or nuclear engineering, or science degree. Senior students preferred.

• Project or co-op experience involving fluid dynamics and heat transfer principles
• Experience with code or software solving 1-dimensional thermal hydraulic systems

• Strong analytical and problem-solving skills
• Working knowledge of any programming language such as C#, C++ or Python
• Extensive knowledge of thermodynamics and heat transfer fundamentals
• Experience with data analysis and validation
• Skills and ability to learn new technology
• Strong problem…