John M. Pfotenhauer Professor Address/E-mail Program Affiliations Courses Education Fields of Interest Publications Summary Files and Links

Contact Information

1329 Engineering Research Building 1500 Engineering Drive Madison, WI 53706-1687

Tel: 608/263-4082 Fax: 608/263-1087 E-mail: pfot@engr.wisc.edu

Program Affiliations

• Mechanical Engineering
• Engineering Physics

• College of Engineering
• Liquid Helium/Nitrogen Facility

Courses

• ME 361: Thermodynamics
• ME 364: Elementary Heat Transfer
• ME 370: Energy Systems Laboratory
• ME 566: Cryogenics
• ME 601: Special Topics in Mechanical Engineering
• NE (NEEP) 562: Applied Superconductivity
• NE (NEEP) 566: Cryogenics
• NE (NEEP) 602: Vacuum Technology

Education

• BA 1979, St. Olaf College
• MA 1981, Physics, University of Oregon-Eugene
• PhD 1984, Physics, University of Oregon-Eugene

Fields of Interest

• cryogenics
• low temperature refrigeration
• applied superconductivity

Publications

• J. Shi, J.M. Pfotenhauer, and G.F. Nellis, “Design Model for a 2-stage Pulse Tube Cryocooler,” Advances in Cryogenic Engineering, vol. 51, AIP, Melville, NY. pp. 329-336 (2006).
• B-Z. Maytal and J.M. Pfotenhauer, “A Unified Perspective of Cryocoolers,” Advances in Cryogenic Engineering vol. 51, AIP, Melville, NY. pp. 557-564 (2006).
• C.B. Hughes, G.F. Nellis, and J.M. Pfotenhauer, "Heat Transfer Coefficient Measurements for Mixed Gas Working Fluids at Cryogenic Temperatures," Cryogenics vol. 45 (8), pp. 546-556 (2005).
• J.M. Pfotenhauer, J.P. Blanchard, and C.J. Martin, “Eddy Current Dissipation in Micro-SMES Bus Bars,” IEEE Transactions on Applied Superconductivity, vol 15 (2), pp. 1939- 1942 (2005).
• L.O. Schunk, G.F. Nellis, and J.M. Pfotenhauer, “Experimental Investigation and Modeling of Inertance Tubes,” Journal of Fluids Engineering, vol. 127 (5), pp.1029-1037 (2005).

Summary

Professor Pfotenhauer co-directs the research activities in the Cryogenics Laboratory, and oversees the operation of the Liquid Helium / Nitrogen Facility.

His research explores the development and application of refrigeration cycles, material properties, and thermal design – all at low temperatures. Cryogenic refrigeration cycles, (cryocoolers) of particular interest include pulse tube refrigerators, mixed-gas Joule-Thomson refrigerators, and various hybrid coolers. Professor Pfotenhauer also explores the integration of cryocoolers for cooling superconducting magnets and electronics, for processing and storing cryogens, and for space applications. He applies the fundamental principles of heat transfer, thermodynamics, and fluid dynamics to address the unique challenges that are encountered in these exciting low temperature applications.

Examples of current interests include developing design methodologies for two-stage pulse tube refrigerators to provide long-term storage of liquid hydrogen, and optimizing the use of cryocoolers to produce solid pellets of deuterium for fusion energy.

Files and Links of Interest

• Absolute Zero Campaign
• International Cryocooler Conference
• Liquid Helium / Nitrogen Facility

Copyright 2008 The Board of Regents of the University of Wisconsin System Date last modified: 23-Jan-2008 Content by: pfot@engr.wisc.edu Accessibility Web services Thank you for visiting http://www.engr.wisc.edu/me/faculty/pfotenhauer_john.html UPDATE PROFILE