Principal Thermal R&D Engineer

About Johnson Controls

Johnson Controls, a global leader in thermal management, mission‑critical building systems, energy efficiency, and decarbonization, helps customers use energy more productively, reduce carbon emissions, and operate with the precision and resilience required in rapidly expanding industries such as data centers, healthcare, pharmaceuticals, advanced manufacturing, and higher education. For more than 140years, Johnson Controls has delivered performance where it really matters. Backed by advanced technology, lifecycle services and an industry‑leading field organization, we elevate customer performance, turn goals into real‑world results and help move society forward. Visit johnsoncontrols.com for more information and follow @Johnsoncontrols on socialplatforms.

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 Control’s 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.

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 hasn't 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 can't. 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 company's 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 candidate's ability to obtain and maintain any required export authorization or eligibility to access controlled items.

Location and Relocation

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.

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.)
• Competitive Bonus plan that will take into account individual, group, and corporate performance.
• Competitive benefits package.
• The posted salary range reflects the target compensation for this role.
• Recognize that exceptional candidates may bring unique skills and experiences that exceed the typical profile.

Benefits

• Competitive Bonus plan that will take into account individual, group, and corporate performance.
• Competitive benefits package.

Technology Support

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.

Equal Employment Opportunity & EEO

Johnson Controls International plc. is an equal employment opportunity and affirmative action employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, age, protected veteran status, genetic information, sexual orientation, gender identity, status as a qualified individual with a disability or any other characteristic protected by law.

To view more information about your equal opportunity and non‑discrimination rights as a candidate, visit EEO is the Law.

Disability Accommodation

If you are an individual with a disability and you require an accommodation during the application process, please visit here.

Johnson Controls: Enhancing the Intelligence of Buildings

Your buildings have a purpose. They are places for people to live or work. Facilities for learning or healing. Venues for entertainment and shopping. Sites for the specialized storage of tangible goods or mission‑critical data. Your buildings have a huge variety of functions; they are central to your mission. This is where Johnson Controls comes in, helping drive the outcomes that matter most. Through a full range of systems and digital solutions, we make your buildings smarter. A smarter building is safer, more comfortable, more efficient, and, ultimately, more sustainable. Most important, smarter buildings let you focus more intensely on your unique mission. Better for your people. Better for your bottom line. Better for the planet. At Johnson Controls, we’ve been making buildings smarter since 1885, and our capabilities, depth of innovation experience, and global reach have been growing ever since. Today, we offer the world’s largest portfolio of building products, technologies, software, and services; we put that portfolio to work to transform the environments where people live, work, learn and play.