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Ralph Budwig, Ph.D., P.E.

Ralph Budwig, Ph.D., P.E.

Professor Emeritus of Mechanical Engineering


Center for Ecohydraulics Research

Mailing Address

322 E Front Street, Suite 340
Boise, Idaho 83702

  • Ph.D., Fluid Mechanics, Johns Hopkins University, 1985
  • B.S., Mechanical Engineering, University of Colorado, 1977

  • Experimental and theoretical fluid dynamics
  • Turbulence, optical, acoustic, and thermal measurements techniques
  • Experimental methods
  • Building energy performance

Ralph Budwig, is a professor in the Mechanical Engineering Department at the University of Idaho in the area of experimental fluid dynamics. He is currently located on the Boise campus of the University of Idaho the director of the Center for Ecohydraulics Stream Laboratory, a $2M+ facility with multi-university participation.

Budwig received his doctorate from Johns Hopkins University in 1985 and has worked as a guest researcher in several laboratories in the United States and Canada since that time. His areas of specialization include experimental and theoretical fluid dynamics; turbulence; optical, acoustic, and thermal measurements techniques; and experimental methods. Budwig has taught extensively in the experimental methods area including required undergraduate courses as well as a specialized graduate level course on the subject of experimental methods in fluid dynamics.

  • William Basham, Ralph Budwig, and Daniele Tonina, “Particle Seeded Grains to Identify Highly Irregular Solid Boundaries and Simplify PIV measurements.” In press in Hydrosphere in July of 2019.
  • Simonetta Rubol, Daniele Tonina, Lionel Vincent, William Basham, Ralph Budwig, Pratixa Savalia, Eva Kanso, Douglas G. Capone and Kenneth H. Nealson. 2018 Seeing through porous media: interstitial flow unveiled. Hydrological Processes, 32(3), 402-40, DOI: 10.1002/hyp.11425
  • Richard S.Skifton, Ralph S. Budwig, John C. Crepeau, and Tao Xing. 2017 Entropy generation for bypass transitional boundary layers. ASME Journal of Fluids Engineering, 139, 13 pages.
  • Tracie R. Jackson, Sourabh V. Apte, Roy Haggerty, and Ralph Budwig, “Flow structure and mean residence times of lateral cavities in open channel flows: influence of bed roughness and shape,” Journal of Environmental Fluid Mechanics, 32 pages, Published online: April 1, 2015, DOI 10.1007/s10652-015-9407-2
  • Budwig, R. & Goodwin, P. 2012 The Center for Ecohydraulics Research Mountain StreamLab – a facility for collaborative research and education. In W. Aung, V. Ilic, O. Mertanen, J. Moscinski, & J. Uhomoibhi (Eds.), Innovations 2012: world innovations in engineering education and research (pp. 17 – 28). Potomac, Maryland, USA: iNEER.
  • Conder, Thomas T., Skifton, Richard S., and Budwig, Ralph S.  “Particle image velocimetry measurements in a representative gas-cooled prismatic reactor core model: Flow in the coolant channels and interstitial bypass gaps,” ASME Publication IMECE2012-87549, November 9 -15, 2012, Houston, Texas.
  • Ralph S. Budwig, Michael J. Anderson, Gabriel Putnam, and Chris Manning. 2010 Ultrasonic particle size fractionation in a moving air stream.  Ultrasonics, 50, 26-31.
  • Stephens, Terrance L. and Budwig, Ralph S. 2007 Three-axis acoustic device for levitation of droplets in an open gas stream and its application to examine sulfur dioxide absorption by water droplets.  Rev. Sci. Instrum., 78, 01490-1 to 11490-8.
  • Egelhoff, C.J., Budwig, R.S., Elger, D.F., Khraishi, T.A., and Johansen, K.H. Model studies of flow in abdominal aortic aneurysms during resting and exercise conditions. J. Biomechanics, 32, 1319-1329 (1999)
  • Elger, D.F., Blackketter, D.M., Budwig, R.S., and Johansen, K.H. 1996. The influence of shape on the stresses in model abdominal aortic aneurysms. ASME Journal of Biomechanical Engineering 118, 326-332.
  • Budwig, R. 1994. Refractive index matching methods for liquid flow investigations. Experiments in Fluids 17, 350-355

  • Physical modeling of the hyporheic zone
  • Modeling of building energy performance
  • Transitional boundary layers studies with elevated free-stream turbulence forcing
  • Characterization of best practice hydraulic conditions for Lamprey passage structures

  • Donald Crawford Graduate Faculty Mentoring Award, 2020
  • Invited speaker at Notre Dame, 2018
  • Invited speaker at ISHMMT conference in Nanjing, China, 2018
  • Outstanding Faculty Member, College of Engineering, University of Idaho, 2016
  • Invited table leader at Idaho SBOE Stem Summit, 2015
  • Invited to be GLC Council Member, 2015
  • Special Recognition at 2013 and 2015 University of Idaho Boise Commencement
  • Special Recognition at University of Idaho Commencement, Boise, May 1, 2013
  • Invited speaker at Discovery Center of Idaho Adult Night in 2013
  • Invited lecture at Kangwon National University (KNU) in Chucheon, South Korea in 2006
  • Office of Naval Technology Research Fellowship, Naval Postgraduate School, 1989 calendar year
  • Institute Fellowship, The Johns Hopkins University, Spring 1978-Fall 1984
  • Graduated with special honors, University of Colorado, 1977

Contact Us

Engineering Physics Building Rm. 324K

Mailing Address:

Mechanical Engineering
University of Idaho
875 Perimeter Drive MS 0902
Moscow, ID 83844-0902

Phone: 208-885-6579