TSSD Services, Inc. (TSSD) was founded in 1999 and is a leading provider of professional and technical staffing solutions. TSSD currently maintains experienced professionals, providing services in the energy and utility sectors, with a focus on the nuclear industry.  
TSSD excels in decommissioning and environmental remediation, expertly managing decontamination, demolition, and site remediation projects. We handle the segregation, packaging, and disposal of low-level radioactive, hazardous, and clean demolition wastes, ensuring safe and efficient outcomes every time.  
Our experienced team has a proven track record of successfully managing safe, efficient, and cost-effective projects.  
 
 
ABOUT THE ROLE 
 
 
TSSD is seeking experienced Fuel Engineers to support a U.S. fuel manufacturer on analysis, design, and optimization of fuel and core systems. Successful candidates will bring depth in one or more of the following disciplines: 

- Thermal/Mechanical - Heat transfer, thermodynamics, structural mechanics 

- Hydraulic - Fluid dynamics, core/fuel assembly hydraulics, system behavior 

- Safety Analysis - Transient/accident analysis, licensing basis assessments 

- Codes & Methods - Development, application, verification & validation of analytical methods and software 
Work is performed, primarily remotely, with sporadic travels as needed for integration, reviews, or on-site coordination. 
 
Key Responsibilities 
 
- Fuel performance & design analysis: Evaluate fuel and component behavior under normal, AOO, and accident scenarios; quantify margins and identify design improvements. 

- Thermal hydraulic modeling: Build and maintain models for core/assembly flow, pressure drop, CHF/MDNBR, and heat transfer; perform sensitivity/uncertainty studies. 

- Safety & licensing support: Execute transient/accident analyses (e.g., LOCA, RIA, loss of flow/heat sink); prepare inputs for safety case and regulatory submittals. 

- Codes & Methods: Apply and (as assigned) enhance validated analysis methods; perform model V&V, document assumptions and biases, and maintain configuration control under quality procedures. 

- Technical documentation: Produce clear calculation files, engineering memos, and customer facing technical reports; present results to internal and client design authorities. 

- Data & testing: Define or review test plans, analyze test data, and reconcile model to test results for model improvement. 

- Cross functional collaboration: Work with fuel design, materials, thermal hydraulics, manufacturing, and safety/licensing teams to drive integrated solutions. 

- Standards & compliance: Follow applicable industry codes/standards and internal QA practices; contribute to continuous improvement of engineering workflows. 

- BS in Nuclear, Mechanical, Chemical, or related Engineering (MS/PhD preferred for Safety Analysis or Methods roles). 

- 3+ years directly relevant experience in at least one focus area: Thermal/Mechanical, Hydraulic, Safety Analysis, or Codes & Methods. 

- Hands on experience with engineering analysis and model development; proficiency in data analysis and scripting (e.g., Python/Matlab) and version control (e.g., Git). 

- Background with fuel performance, core thermal hydraulics, or safety analysis for light water reactors or comparable technologies. 

- Experience preparing inputs for licensing or interacting with customer/regulatory stakeholders. 

- Familiarity with common industry codes and solvers (examples may include fuel performance, TH system, sub channel, neutronics, or Monte Carlo tools), and with QA governed engineering processes. 

- Knowledge of materials behavior (e.g., fuel, cladding, structural materials) under irradiation and thermal mechanical loads. 

- Strong communication and collaboration skills in a multi-disciplinary, remote environment.