Doug Bohl
Assistant Professor
239 CAMP
Clarkson University
PO Box 5725
Potsdam, NY 13699-5725
Phone: 315-268-6683
Fax: 315-268-6695
E-mail: dbohl@clarkson.edu
CV: PDF
Educational Background
B.S., University of Connecticut (1992)
M.S., Michigan State University (1996)
Ph.D., Michigan State University (2002)
Teaching
ES330 - Fluid Mechanics
Research Interests
Dr. Bohl’s research interests are in the development and application of new diagnostic techniques for measurement of fluid flows. His background includes: unsteady aerodynamics, flow control, low Reynolds number mixing, spill and dispersion of volatile chemicals and dynamics of energetic materials.
Molecular Tagging Velocimetry (MTV)
In order to better understand the dynamics of fluid systems measurement techniques must be developed to visualize the flow fields. MTV is a whole field optical measurement technique that relies upon molecules that are premixed in the fluid medium that can emit light when excited by photons at the proper wave length. In this technique the patterns are written into the flow medium. Two images are taken during the lifetime of the molecule displacement of the small fluid region is determined via image correlation techniques. The velocity fields are determined knowing the displacement and time between the images.
The above images are a MTV image pair from a vortex ring impinging on a wall. The velocity vectors are the resultant velocity field from the images. (Gendrich et al. 1997)
Polymeric Mixing
Mixing is typically caused by large scale motions in flows associated with turbulence. In the processing of polymers the small scale motions are not available because of the high viscosity of these materials. In this case mixing is a result of large scale stirring action. The quality of the final product is highly dependant upon the homogeneity of the mixture. Currently there is interest in understanding the underlying physics of mixing at low Reynolds number so that more efficient mixing processes can be developed. We are applying optical measurement techniques such as Particle Image Velocimetry (PIV) to these flows to map out the velocity and mixing fields.
The images show the measured vorticity and mixing fields in a simple batch mixer. Motion is driven by the rotation of a flat blade shown by the purple line. Re = 109.
Heat Transfer at the Air/Water Interface
Understanding global climate dynamics is a problem that must be addressed so that we can predict and address problems associated with global warming. The interface between the air and seas provide the major mechanism for heat exchange on a global level. Using MTV we are studying the interaction of fluid structures at the air/water interface and how they affect heat transfer between the atmosphere and ocean.
Selected Publications
D.G. Bohl, “Experimental Investigate of the Fluid Motion in a Batch Mixer Driven by a Flat Plate Impeller”, Submitted Journal of Fluids Engineering, October 2005.
D.G. Bohl, G. Jackson, “Experimental Study of the Spill and Vaporization of a Volatile Liquid”, Journal of Hazardous Materials, In-Press.
D.G. Bohl, R.J. Volino, “Experiments With Three Dimensional Passive Flow Control Devices on Low Pressure Turbine Airfoils”, Journal of Turbo Machinery, Vol. 128, pp. 251-260 April 2006.
D.G. Bohl, M.M. Koochesfahani, “MTV Measurements of Axial Flow in a Concentrated Vortex Core”, Physics of Fluids, Vol. 16, No. 11. pp. 4185-4191, 2004.
D.G.Bohl, Experimental Study of the 2-D and 3-D Structure of a Concentrated Line Vortex Array, Michigan State University, Doctoral Dissertation, 2002.
D.G.Bohl, M.M.Koochesfahani, B.J.Olson, “Development of Stereoscopic Molecular Tagging Velocimetry”, Experiments in Fluids, Vol. 30, No.3, pp 302-308, 2001.
D.G.Bohl, J.F.Foss, “Near Exit Plane Effects Caused by Primary-Plus-Secondary Tabs”, AIAA Journal, Vol. 37, No.2, pp.192-201, 1999.
Selected Conference Proceedings
R.J. Lee, K.E. Newman, D.T. Knutson, N. M. McGregor, D.G. Bohl, “Combined Air Blast and Quasi-Static Overpressure Assessment for Pressed Aluminized Explosives”, Proceedings of the 13th International Detonation Symposium, Norfolk, VA, July 23-28, 2006.
D.G. Bohl, R.J. Lee, “Study of the Break-Up and Impact of a Metal/Polymer Composite Material in a Two-Step Process”, Proceedings of the 37th International ICT Conference, Karlsruhe, Germany, June 27-30, 2006.
R.J. Lee, W. Mock, J.R. Carney, W.H. Holt, G.I. Pangilinan, R.M. Gamache, J.M. Boteler, D.G. Bohl, J. Drotar, G.W. Lawrence, “Reactive Materials Studies”, Proceedings of the 14th APS Topical Conference on Shock Compression of Condensed Matter, Baltimore, MD, July 31-August 5, 2005.
R.J. Volino, D.G. Bohl, “Structure of Oscillating Vortex Generator Jets”, Proceedings of the 4th International Symposium on Turbulence and Shear Flow Phenomena, Williamburg, VA, June 27-29, 2005.
D.G. Bohl, R.J. Volino, “Experiments With Three Dimensional Passive Flow Control Devices on Low Pressure Turbine Airfoils”, Proceedings of ASME Turbo Expo 2005, Paper GT2005-68969, Reno, NV, June 6-9, 2005.
R.J. Volino, D.G. Bohl, “Separated Flow Transition Mechanism and Prediction with High and Low Freestream Turbulence Under Low Pressure Turbine Conditions”, Proceedings of ASME Turbo Expo 2004, Paper GT2004-53360, Vienna, Austria, June 14-17, 2004.
D.G.Bohl, M.M.Koochesfahani, “MTV Measurements of the Flow Structure Downstream of an Oscillating Airfoil”, AIAA-Paper 2003-4017, 2003.
D.G.Bohl, M.M.Koochesfahani, “MTV Measurements of Axial Flow in Concentrated Vortex Cores”, AIAA-Paper 2003-0425, 2003.
M.M.Koochesfahani, D.G.Bohl, “Molecular Tagging Visualization and Velocimetry of the Flow at the Trailing Edge of an Oscillating Airfoil”, Proceedings of the 10th International Symposium on Flow Visualization, Kyoto Japan, August 26-29, 2002.
C.Somerton, D.Bohl, M.Crimp, "Development of an Engineering Teaching Certificate Program", Proceedings of the ASEE 2000 Spring Conference North Central Section, Michigan State University, East Lansing, MI, March 30-April 1, 2000.
C.P.Gendrich, D.G.Bohl, M.M.Koochesfahani, “Whole-Field Measurement of Unsteady Separation in a Vortex Ring/Wall Interaction”, AIAA Paper 97-1780, 1997.