Principal Thermal R&D Engineer

What you will do

Johnson Controls is hiring! As Principal Thermal R&D Engineer, you'll be a senior technical contributor driving research and development of next-generation thermal management devices built on Johnson Controls patented Stack Forging process. You'll own the technical direction of our research programs including identifying promising cooling technologies and device architectures, building and testing prototypes, and maturing them to the point where they can be handed off for commercialization. The devices you develop will go directly into the systems where thermal limits are being pushed hardest.

You'll work closely with the Customer Solutions team and the wider Johnson Controls organization to understand where our customers' thermal challenges are heading and how our technology roadmap should respond. You'll translate those needs into a research portfolio, define and execute the projects within it, and serve as the technical authority on thermal-fluid performance across the company.

This position is based onsite at our Alloy location in Burlington, MA. Candidates must be commuting distance to the facility, or able to relocate. Various relocation packages are available. Candidates that are US citizens and/or Permanent Residents of the United States will only be considered.

Who you are

You're a deep thermal-fluids expert who is equally comfortable at a test bench and inside a CFD model. You've taken cooling concepts from whiteboard to working hardware, and you understand single- and two-phase heat transfer, pressure drop, and flow distribution well enough to know which internal geometries will matter before you simulate them. You know how to design an experiment that gives a clean answer, and you distrust a simulation that hasnt been validated against one.

You're self-directed and hands-on. You're comfortable with the ambiguity of research and disciplined enough to know when a technology is ready to leave the lab.

How you will do it

• Partner with the Solutions team and Johnson Controls stakeholders to identify emerging customer thermal requirements and cooling technologies, and shape the thermal technology roadmap to meet them.
• Scope and propose research projects with clear hypotheses, success criteria, timelines, and resource needs; secure alignment with leadership and report on progress.
• Conceive novel thermal device architectures that exploit the internal microgeometry freedom of Stack Forging to deliver performance conventional manufacturing cant.
• Work with our simulation team to complete CFD and thermal-fluid analysis to screen concepts, predict performance, and guide design iteration ahead of hardware builds.
• Advance the companys capability in two-phase and refrigerant-based cooling, including boiling and condensation behavior, flow stability, and working fluid selection.
• Design and build test rigs, define test protocols, execute experiments, and analyze data to validate device performance and quantify uncertainty.
• Act as the technical authority on thermal performance; review designs, mentor engineers, and set the standard for analytical and experimental rigor.

What you will need
Required

• PhD in Mechanical Engineering, Thermal-Fluid Sciences, or a related field with 8+ years of experience, or an MS/BS with 12+ years of experience in thermal management R&D.
• Deep expertise in heat transfer and fluid mechanics, including single-phase liquid cooling and two-phase or refrigerant-based systems.
• Proficiency with CFD and thermal-fluid simulation tools (e.g., Siemens SimCenter, ANSYS Fluent, COMSOL) and a track record of validating models against experimental data.
• Hands-on experience designing, building, and operating thermal test rigs and instrumentation, including flow loops, temperature and pressure sensing, and data acquisition.
• Demonstrated success taking thermal technologies from concept through prototype to production-ready or commercial launch.
• Experience defining and leading research projects, including scoping, budgeting, and presenting results and recommendations to senior leadership.
• US Citizen and/or Permanent Resident

Preferred

• Experience with liquid cooling for AI/HPC data center hardware, semiconductor equipment, power electronics, or defense systems.
• Familiarity with metal additive manufacturing, brazing, diffusion bonding, or other processes that produce complex internal geometries, and an understanding of their manufacturability constraints.
• Publications or patents in thermal management, two-phase cooling, or heat exchanger design.
• Experience with electronics packaging, thermal interface materials, and chip-level heat flux considerations.
• Proficiency with Python or MATLAB for data analysis and reduced-order modeling; familiarity with CAD (Onshape preferred).
• Experience working with technology readiness or stage-gate frameworks, and with research collaboration inside a larger parent organization.

Export Control Requirement: This position may require access to information, technology, technical data, software, or other items subject to U.S. export control laws and regulations. Any offer of employment for this position may be contingent upon the candidates ability to obtain and maintain any required export authorization or eligibility to access controlled items.

SALARY RANGE: $130,000 - $165,000 (Salary to be determined by the education, experience, knowledge, skills, and abilities of the applicant, internal equity, and alignment with market data.) This role offers a competitive Bonus plan that will take into account individual, group, and corporate performance.  This position includes a competitive benefits package. The posted salary range reflects the target compensation for this role. However, we recognize that exceptional candidates may bring unique skills and experiences that exceed the typical profile. If you believe your background warrants consideration beyond the stated range, we encourage you to apply. To support an efficient and fair hiring process, we may use technology assisted tools, including artificial intelligence (AI), to help identify and evaluate candidates. All hiring decisions are ultimately made by human reviewers. For details, please visit the About Us tab on the Johnson Controls Careers site at

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