Co-Simulation Engineer III

Position Title: Co-Simulation Engineer III 

Position Location: Remote - work virtually from most locations in the United States 

Job Summary 

The Co-Simulation Engineer III will have the opportunity to work with and collaborate with senior design staff to develop multi-domain co-simulation and digital twin capabilities for data center design and construction. The role also includes computational fluid dynamics (CFD) modeling of the data center and its associated internal and external environments.  This person will work as part of the Engineering Team and interact closely with the Project Management Team to produce hydraulic network models, CFD models, digital twin applications, and QC design specifications through engineering modeling. 

The Co-Simulation Engineer III will receive limited direction on day-to-day work and general instruction on new projects or assignments. Will execute and assist project leadership on projects of complex scope. Will work independently or under limited supervision. 

The Co-Simulation Engineer III will communicate and operate in line with organizational goals and values, as well as departmental objectives. 

Essential Functions 

Co-Simulation Planning and Requirements Definition (10%) 

• Coordinate closely with design teams to define co-simulation objectives, key performance metrics, and acceptance criteria, ensuring a comprehensive understanding of project requirements. 

• Participate in discussions to define modeling prerequisites, collect necessary design and operational data, and establish appropriate assumptions and initial conditions for simulations. 

• Identify coupling strategies and model boundaries (1D network, 3D CFD, controls), anticipate challenges, and recommend modifications to design parameters or modeling approach to improve efficiency and fidelity. 

Develop and Integrate Multi-Domain Co-Simulation Models (60%) 

• Independently develop thermo-hydraulic (flow-network) models for chilled water and liquid cooling systems (pumps, valves, heat exchangers, CDUs, manifolds, cold plates). 

• Build and maintain system-level models for steady-state and transient response, including redundancy/failure-mode scenarios and control logic impacts. 

• Develop co-simulation interfaces between 1D networks and 3D CFD/thermal models and manage data exchange, time steps, and convergence. 

• Perform pressure drop, flow balancing, and heat rejection analyses to validate design intent and support equipment selection and sizing. 

• Utilize hydraulic modeling tools such as Flownex (highly desired), Siemens Flomaster, Aspen HYSYS or equivalent, and maintain working knowledge of CFD tools (at least one) such as Cadence Reality DC Design, ANSYS Fluent and STAR-CCM+. 

• Create and curate simulation-ready system schematics, component libraries, and metadata to support reusable model assets and digital twin workflows. 

• Develop and/or review model setup including boundary conditions, solver settings, co-simulation time steps, and quality checks appropriate for the intended use case. 

• Review and/or prepare detailed co-simulation reports documenting assumptions, methodology, results, and actionable design recommendations. 

• Assist in developing proposals including modeling scope, schedule, and budget. 

• Conduct technical discussions with clients and internal stakeholders, presenting modeling findings, interpreting results, and providing engineering recommendations. 

• Timely and effective management of modeling tasks, including resource forecasting, coordination, and version control of model assets and scripts. 

• Perform QAQC peer reviews for co-simulation models where he or she is not the lead analyst. 

Guide and Direct Validation, Calibration, and Commissioning Support (20%) 

• Conduct rigorous validation and calibration of system/co-simulation results using analytical techniques and real-world data to ensure models are accurate and fit for purpose. 

• Collaborate with design, commissioning, and operations teams to collect and reconcile site data (BMS/SCADA, flow/temperature/pressure measurements) for model calibration. 

• Prepare validation and calibration reports comparing model predictions with measured data, documenting uncertainty, limitations, and performance envelopes. 

• Work with the CFD team and interact closely with the project management team to ensure alignment between system models, CFD models, and design intent. 

• Review and respond to technical queries related to modeling assumptions, co-simulation results, and design implications. 

• Review and complete validation checklists and documentation; contribute to modeling standards and continuous improvement initiatives. 

• Review and approve model updates based on validation findings and project changes. 

Reporting (10%) 

• Prepare project progress reports, issue logs, and model status updates for internal and external stakeholders. 

• Update and maintain model libraries, coupling scripts, and project documentation (assumptions log, revision history, RFI responses as applicable). 

• Manage personal hours using company tools.