Wisconsin Discovery Portal

Researcher's Profile

Last Name


First Name


Middle Initial

Areas of Research Expertise

* Cryogenic refrigeration systems including mixed gas JT systems, reverse-Brayton systems , pulse-tubes, and hybrid cryocoolers
* Thermal-fluid problems in semiconductor manufacturing including immersion lithography, EUV lithography, and nanoimprint
* Vortex tube theory and application
* Refrigeration technology
* Gas bearing supported turbomachinery

Web site

Gregory Nellis' University Webpage 

Curriculum Vitae (CV)


Current/Active Funding

  • DOD, Navy, 2008-2012, Fundamental Challenges for Low Temperature Pulse Tubes
  • DOE, 2010-2013, ARRA Optimization of Regenerators for AMRR Systems
  • Strategic polymer Sciences, 2010-2012, Development of Electrocaloric Cooling Systems

Issued Patent(s)

  • 7,789,371 - Low-power piezoelectric micro-machined valve, granted Sept 2010.

USPTO Published Applications

Recent Publication(s)

  • "Experimental evaluation of an adaptive Joule-Thomson cooling system including silicon-microfabricated heat exchanger and microvalve components"

Zhu WB, Park JM, White MJ et al., Journal of Vacuum Science & Technology A 29 (2): Mar-Apr 2011. This article reports the evaluation of a Joule-Thomson (JT) cooling system that combines two custom micromachined components-a Si/glass-stack recuperative heat exchanger and a piezoelectrically actuated expansion microvalve.

  • "An Experimentally Validated Numerical Modeling Technique for Perforated Plate Heat Exchangers"

White MJ, Nellis GF, Klein SA, et al., Journal of Heat Transfer 132 (11): 111801 Nov 2010.  This paper presents a numerical model of a perforated plate heat exchanger that accounts for axial conduction, external parasitic heat loads, variable fluid and material properties, and conduction to and from the ends of the heat exchanger.

  • "A Si/glass bulk-micromachined cryogenic heat exchanger for high heat loads: fabrication, test and application results"

Zhu WB, White MJ, Nellis GF, et al., Journal of Microelectromechanical Systems 19 (1): 38-47 Feb 2010. This paper reports on amicromachined Si/glass stack recuperative heat exchanger with in situ temperature sensors.

  • "A microvalve with integrated sensors and customizable normal state for low-temperature operation"

Park JM, Evans AT, Rasmussen K, et al., Journal of Microelectromechanical systems 18 (4): 868-877 Aug 2009. This paper reports on design, fabrication, and testing of a piezoelectrically actuated microvalve with integrated sensors for flow modulation at low temperatures. One envisioned application is to control the flow of a cryogen for distributed cooling with a high degree of temperature stability and a small thermal gradient.

Recent Artistic Works




Research Tools


Research Facilities

  • Computational Mechanics Center
  • Solar Energy Laboratory

E-mail Address


Phone Number

(608) 265-6626 

Current University

UW - Madison 


Mechanical Engineering 


Associate Professor 

Other Appointments


Address Line 1

1339 Engineering Research Building 

Address Line 2

1500 Engineering Drive 





Zip Code


Bachelor's Degree

BS, University of Wisconsin-Madison, Mechanical Engineering, 1992

Master's Degree

MS, Massachusetts Institute of Technology, Mechanical Engineering, 1995


PhD, Massachusetts Institute of Technology, Mechanical Engineering, 1997

Other Degrees


Technologies Available for Licensing

Created at 7/19/2007 2:53 PM  by Mindy Dawson 
Last modified at 11/7/2011 11:28 AM  by EXTWEB\rshea