Sr. Thermal Systems Engineer

Flex (Flextronics)

Quick summary

Work type: On-site
Location: Littleton, MA
Salary: $126,500–$173,900 / yr
Posted: 26 days ago
Closes: Jul 24, 2026

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Salary context

Competitive pay

How this pay compares to similar roles

Similar $163k

This role $150k

$118k most similar roles pay here $202k

This role pays less than 63% of similar roles. Most pay $132,500–$193,000 — the shaded band above. At the midpoint, this role pays about $150k versus about $163k for comparable roles.

Based on 239 similar postings.

Employer

About Flex (Flextronics)

Flex (formerly Flextronics) is a global technology, supply chain, and manufacturing solutions provider helping companies design, build, and deliver products across industries. Industry: Electronics Manufacturing Services

Flex (Flextronics) currently has 9 open roles on FindRole.

Listed pay typically runs $126,500–$173,900 across 7 roles with salary data.

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View all roles at Flex (Flextronics)

At a glance

TL;DR · Sr. Thermal Systems Engineer

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As a Senior Thermal Systems Engineer at JetCool in Littleton, MA, you will lead the technical development of direct-to-chip cooling systems for high-performance computing environments, collaborating closely with cross-functional teams including Product Management, Mechanical and Electrical Engineering, Manufacturing, Quality, Reliability, and key customers. Your responsibilities include defining system-level thermal requirements, conducting detailed analysis using tools like FloEFD and ANSYS Fluent, designing liquid cooling subsystems, validating performance through rigorous testing, and ensuring seamless transition from prototypes to mass production. You will need a strong background in Mechanical or Aerospace Engineering with extensive experience in thermal design and validation for high-power electronics, proficiency in CFD and thermal metrology, hands-on lab instrumentation skills, and the ability to drive product development from EVT to PVT stages. This role is pivotal in advancing JetCool’s mission to redefine cooling standards for sustainable data centers at scale.

Skills

Python LabVIEW CFD ANSYS Fluent FloEFD Icepak MacroFlow COMSOL DFX HALT/HASS FMEA 8D/PPS DAQ GALILEO

What you'll do

Define system-level thermal requirements for D2C cooling systems.
Build and validate 1D/3D models for liquid cooling components using CFD software.
Specify and refine cold plates, CDUs, manifolds, and other subsystems.
Develop test plans and execute lab/rack-scale testing for thermal performance.
Drive failure analysis and corrective actions to ensure long-term reliability.

What we're looking for

BS/MS in Mechanical Engineering or Aerospace Engineering with 5+ years of thermal design/validation experience.
Expertise in fluid dynamics, thermodynamics, heat transfer, and liquid cooling systems.
Proven ability to develop and validate 1D/3D thermal models using CFD software.
Hands-on experience with lab instrumentation for thermal performance testing.
Strong background in product development from EVT to PVT stages.
Excellent technical communication and documentation skills.

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