/College of Engineering and Applied Sciences
Department of Mechanical Engineering

Jon Longtin, PhD, PE

Jon LongtinProfessor

Office: Light Engineering 135

Email Address: jon.longtin@stonybrook.edu

Phone Number: (631) 632-9436

Bio:

Jon Longtin joined the Mechanical Engineering Faculty at Stony Brook in Fall 1996. His research interests include using the unique qualities of laser light for novel measurement of the thermophysical behavior of liquid and solids. Examples include measuring the surface temperature and concentration of a liquid and determining a liquid's thermophysical properties, e.g., specific heat and thermal conductivity. Another of his interest areas is fundamental and applied aspects of ultra high intensity, short-pulse laser interactions with liquids and solids for laser material processing, where behavior far different than that observed at lower, more moderate laser intensities can occur. Longtin is the author of over thirty publications, including invited chapters in Microscale Energy Transport and Annual Review of Heat Transfer. He is currently a member of the ASME K-15 committee, Heat Transfer in Manufacturing and Materials Processing. Longtin is the recipient of the 1996 JSPS Postdoctoral Fellowship, 1997 NSF CAREER and PECASE awards, and the 1998 Excellence in Teaching Award. His research is funded by the National Science Foundation, NASA, and other sources. 

Education:

  • University of California, Berkeley, Ph.D. 1995
  • University of Cincinnati, Cincinnati, M.S. 1991
  • University of Cincinnati, Cincinnati, B.S. 1989

Professional Experience:

  • Department of Mechanical Engineering, Stony Brook University, 1996-Present
  • Interim Chair, Mechanical Engineering, Stony Brook University 
  • Professional Engineer, New York State

Awards & Publications: 

  • Recipient of the 1998 Excellence in Teaching Award. 
  • Recipient of the 1997 NSF CAREER and PECASE awards,
  • Recipient of the 1996 JSPS Postdoctoral Fellowship, 

Professional Memberships & Service: 

  • Fellow, American Society of Thermal and Fluid Engineers (ASTFE) 
  • Chair of the Executive Committee for the American Society of Thermal and Fluid Engineers (ASTFE) (2025 - Present) 
  • Founding Vice-chair for the Executive Committee for the American Society of Thermal and Fluid Engineers (ASTFE) 2022-2025
  • Registered Professional Engineer in New York State. 
  • Member of the ASME K-15 committee, Heat Transfer in Manufacturing and Materials Processing.

Overview: 

Jon Longtin conducts research in the thermal sciences, with a focus on developing laser-based optical measurement techniques for temperature, concentration, and thermal properties; using ultra-fast lasers for precision materials processing and micromachining, and the development of sensors for harsh environments using direct-write thermal spray technology, including thermistors and thermocouples for temperature, resistance gauges, and humidity sensors. Dr. Longtin is a registered Professional Engineer in New York State. 

Highlights & Accomplishments:

  • Invented World’s First Heat Flux Sensor in a Thermal Spray Coating (Patented, Licensed and Commercialized)
  • Developed Novel Laser-Machined Thermal Spray Thermoelectric Generator
  • Invented Low-Cost Convection Solution for Low-Temperature Baseboard Heating

Research Interests:

  • Medical Devices and Prototyping
  • Thermal Storage and Heat Pipes
  • AI/ML Applied to the Thermal Sciences