CFD Engineer - Thermal Design for Power Electronics Cooling

Thermal Design

Role Summary

The CFD Engineer will be responsible for performing thermal simulations and provide solutions to support the design of power electronics converters, including AC-DC, DC-DC, DC-AC inverters, On-board/Off-board chargers, BESS modules, and EV traction converters.
The role focuses on electronics cooling, heat sink design, cold plate development, airflow path optimization, and thermal performance validation to ensure high reliability and efficiency of power electronics systems.

Key Responsibilities

1. CFD Analysis for Power Electronics

• Perform detailed thermal simulations for High-density converter enclosures having:

– SiC MOSFET/IGBT power modules
––inductors, transformers

– Heat sinks, cold plates and vapor chambers

• Identify semiconductor junctions, hot spots
• Conduct steady-state and transient analysis to capture dynamic thermal behaviour.

2. Cooling System Design & Optimization

• Model and optimize:
  – Forced air cooling (fans, blowers, ducts)
  – Liquid cooling (cold plates, microchannels)
  – Natural convection solutions
  – Hybrid cooling architectures (air + liquid)
• Selection of cooling medium and type of coolant
• Analyze pressure drop, coolant flow distribution, and thermal resistance.

3. Converter Packaging & Layout Input

• Work with electrical & mechanical teams to influence:
  – Component placement for minimal thermal stress
  – PCB thermal vias, copper pours, hot spot mitigation
  – Heat spreading elements (thermal pads, gap fillers)
  – Busbar & enclosure thermal management
• Support compact converter packaging and weight optimization.

4. Meshing, Pre-Processing & Simulation Setup

• Prepare detailed CFD models:
  – Clean CAD geometry (SiC module, heatsink fins, ducts, cold plates)
  – Generate high-quality meshes (inflation layers, refinement zones)
  – Define appropriate boundary conditions, material properties, and solver settings
• Ensure accurate modelling of conjugate heat transfer.

5. Validation, Correlation & Testing Support

• Correlate CFD predictions with lab measurements:
  – Thermocouples & IR camera results
  – Junction-to-case and case-to-ambient temperature
  – Fan curves and coolant performance

-- And update the models/assumptions

• Support prototype testing and thermal characterization.

6. EMI/Environmental Derating Considerations

• Analyze thermal behavior under:
  – High ambient temperatures
  – Altitude derating
  – Dust, humidity, vibration conditions
• Support compliance with indusrtrial standards like 

7. Design Recommendations & Reporting

• Provide actionable thermal design inputs:
  – Heatsink fin geometry that can be manufactured
  – Cold plate channel optimization
  – Component placement
  – Fan/blower specifications
  – Material and coating selection
• Prepare clear, data-driven reports for design reviews.

8. Cross-Functional Collaboration

• Work closely with:
  – Power electronics design team
  – Mechanical design team
  – PCB layout engineers
  – System engineering
  – Testing & validation teams
•  
• Participate in design reviews (DR1–DR4) and gate reviews.

Technical Skills

• Strong understanding of heat transfer, fluid dynamics, conduction/convection/radiation.
• Experience with cooling design for high-power electronics:
  – 5 kW to MW-level converters
  – IGBT/SiC/GaN fast-switching devices
• Hands-on expertise in CFD software:
  – ANSYS Icepak / Fluent
  – Siemens Star-CCM+
  – Simcenter FloEFD
  – COMSOL / OpenFOAM (optional)
• Knowledge of power electronics basics is a strong plus:
  – PFC, LLC, PSFB, Inverters
• Experience with Fan/Blower selection, coolant loop design, and thermal resistance modelling.
• Experience in validation of design.
• Knowledge of heatsinks, fans and latest solution available in market

Tools & Skills

• CAD tools (SolidWorks, Creo, NX).
• Meshing tools (ANSYS Mesher, SpaceClaim, SnappyHexMesh, etc.).
• Python/MATLAB for automation (optional).

Qualifications

• B.E / B.Tech / M.E / M.Tech in  Mechanical Engineering, Thermal Engineering  or eqlt.
• Experience Levels 10 years with 5+ yrs on Power Electronics converter cooling
  

Preferred Experience

• Thermal management of:

– High-frequency Power converters

– EV traction inverters
– Onboard/offboard EV chargers
– BESS power modules

• Battery pack cooling design
• Experience with:
  – Cold plate and heat sink co-design
  – Fan/blower curves & thermal derating
  – DVP&R thermal validation
• Understanding of reliability parameters:
  – Junction temperature
  – Thermal cycling
  – Power cycling
  – Mean time to failure