Doug Bohl

Biography

Doug is an avid biker outside of work. He is most at home on his mountain bike riding on the local trails and training for endurance races. In 2013 Doug competed in and finished the Leadville Trail 100, a 100 mile mountain bike race high in the mountains of Colorado. During the winter Doug’s interests switch to the sport of luge where he competes as a Masters athlete, currently acts as the president of the Adirondack Luge Club, and is a race official for the US Luge Association. Doug volunteers in the community as a member of the Potsdam Volunteer Rescue Squad (PVRS) and Search and Rescue of the Northern Adirondacks (SARNAK). Doug and his wife Coreen have two sons, Bailey and Noah. Currently Doug is learning what it is like to be a parent, rather than teacher, of a college student.

Education Background

Ph.D. - 2002 Michigan State University
M.S. - 1996 Michigan State University
B.S. - 1992 University of Connecticut

Courses Taught

ES330 - Fluid Mechanics
AE/ME427 - Design of Propulsion Systems
ES580 - Foundations of Teaching College Engineering

Research Interests

Dr. Bohl's research interests are in the development and application of new diagnostic techniques for measurement of fluid flows. His technical interests include: unsteady aerodynamics, vortex dynamics, multiphase flow fields, and the release and dispersion of volatile/hazardous chemicals.

Development of Optical Diagnostic Tools: Diagnostic tools are critical for an experimentalist. The scope and complexity of the problems being investigated are ever increasing. It is, therefore, imperative that the tools used to study these problems also evolve. The development of optical diagnostic tools like Particle Image Velocimetry (PIV) and Molecular Tagging Velocimetry (MTV) has revolutionized experimental fluid dynamics. These techniques allow for simultaneous measurements over a region in a flow field which in turn allows the experimentalist to observe instantaneous flow structures. Dr. Bohl's research involves the development and advancement of optical techniques for the measurement of fluid flows. He has been an integral part of the multidisciplinary team that developed a novel optical velocimetry technqiue know as Molecular Tagging Velocimetry, expanding the technique to include stereoscopic measurements and quantification of fluid temperature.

Dynamic Stall: When a lifting surface is placed at a sufficiently high angle of attack (AOA), the fluid flow on the low pressure surface separates causing loss of lift and stall. Static stall typically happens at relatively small angles depending on the shape of the airfoil. It has been shown, however, that for surfaces that are undergoing dynamic pitching, the angle at which the lifting surface stalls is considerably higher. This phenomenon is known as dynamic stall. When dynamic stall is encountered, the loss of lift is abrupt resulting in nearly instantaneous loss of lift.

Dr. Bohl’s research group is active in the investigation and quantification of the flow field around airfoils undergoing dynamic stall. The goals of this work are to understand the effects of pitch rate, aspect ratio and tip conditions of the process of dynamic stall and to develop control strategies to mitigate the effects of dynamic stall. Additionally, Dr. Bohl has been investigating the hydrodynamics of airfoils modified based on the flippers of humpback whales. In recent years engineers have begun to utilize the natural world as inspiration for engineering solutions. Humpback whales are recognized for their high degree of maneuverability given their body size. The leading edges of the humpback whale's control surfaces (i.e. its flippers) are characterized leading edge protrusions, or tubercles. Studies of the static lift and drag characteristics of airfoils modeled after the humpback whale's flipper have shown that at angles of attack past the onset of static stall the bio-inspired airfoil showed better performance by "softening" the stall characteristics. It was inferred that the tubercles were inhibiting large scale separation along the low pressure surface. Because Humpback whales use their flippers for dynamic control when swimming and hunting, which are characterized by rapid changes in orientation, Dr. Bohl is investigating the possibility that these bio-adaptations are passive mechanisms for delaying or controlling dynamic stall.

Release and Dispersion of Hazardous Materials: The potential hazards of the transportation of chemicals via rail, road and sea are becoming of interest to many governmental agencies and first responders. This interest is being driven by recent accidents, the increased volume of transportation and because of domestic/international threats. As recent rail accidents have shown, the accidental release of hazardous chemicals can have a significant impact both from loss of life and economic loss standpoints. In the event of a release, protection of the public from these hazards requires real time analysis. Computational simulations are widely used for this analysis; however the key in an emergency is the speed at which the hazard assessment can be made.

Reduced order models are computational codes that simplify the governing equations to gain speed at the expense of not fully accounting for the chemistry and physics of a flow field. Instead these techniques rely on experimentally derived parameters and/or correlations which simulate the physics and chemistry. In many cases the chemicals of interest are highly volatile and/or caustic. They may undergo rapid changes in particle/droplet conditions (e.g. size, shape, state, etc.) due to evaporation, droplet interaction, phase changes, etc. These chemicals pose a difficult problem for low order models as the droplet physics are not well understood and so cannot be adequately modeled. Further, these chemicals are difficult to measure using traditional aerosol sampling techniques due to their caustic nature and the likelihood of changing properties due to physical sampling. Both new techniques to measure the aerosol dynamics and data from controlled experiments are critically needed to develop and validate these computational models.

Dr. Bohl is currently involved in the development of an optical technique to quantify the aerosol conditions (size, shape, speed, etc.) at a location in the plume of a large scale chemical release. He is currently applying the technique to large scale atmospheric releases with other collaborators.

Flow Induced by Plasma Discharge: Plasmas formed directly in and contacting a liquid are a powerful source of reactive radicals, ions and electrons. Because of their high reactivity, these species have been used to purify drinking water, sterilize food, create new materials, and for applications in plasma medicine. As an example, to purify contaminated water, using only electricity, plasmas split liquid water into powerful radicals and create electrons which are capable of completely destroying toxic molecules. For an environmental group of pollutants with carcinogenic properties called perfluorinated compounds, plasmas have been shown to be the only technology available capable of completely destroying these compounds. Therefore, the development of a plasma-based technology that will rapidly degrade contaminants of emerging concern before they are released into rivers and drinking water supply networks is essential for improving the quality of life.

The goal of this collaborative research project is to quantify the physical and chemical processes occurring at plasma-liquid interfaces. The project combines plasma chemistry and bulk liquid chemistry measurements with fluid dynamic investigations and molecular dynamics simulations to investigate transport mechanisms of plasma excited species and ions across the interface and quantify the interrelationship of these with the bulk liquid. Two specific goals this multidisciplinary approach will achieve are: (1) Correlation of the bulk liquid transport processes with the plasma-liquid interface dynamics and (2) Determination of the significance of the plasma excited species transport in the kinetics of interfacial chemical processes. The central approach for achieving these goals lies in identifying degradation mechanisms of several organic compounds of environmental and biological importance and applying Particle Image Velocimetry (PIV) and Laser-Induced Fluorescence (LIF) imaging to understand the role bulk transport processes play in the dynamics at the interface.

Awards

NSF CAREER Awardee
John W. Graham, Jr. Faculty Research Award Clarkson University
Tau Beta Pi Faculty Award (Clarkson University)
Clarkson University Teaching Excellence Recognition (2007, 2008, 2009, 2010, 2011)
Michigan State University Excellence in Teaching Citation (University wide award for teaching as a graduate student)
TAU BETA PI , PI TAU SIGMA

Publications

A. Bluestein, R. Venters, D. Bohl, B. Helenbrook, G. Agmadi, “Turbulent Flow Through a Ducted Elbow and Plugged Tee Geometry: An Experimental and Numerical Study”, Journal of Fluids Engineering, Vol. 141(8) DOI:10.1115/1.4042256, January 2019
S. Mededovic Thagard, G. Stratton, M. Vasilev, P. Conlon, D. Bohl, “An Experimental Investigation of the Liquid Flow Induced by a Pulsed Electrical Discharge Plasma”, Invited, Plasma Chemistry and Plasma Processing, Vol. 38(4), DOI: 10.1007/s11090-018-9905-3, July 2018
S. Mededovic Thagard, G. Stratton, F. Dai, C. Bellona, T. Holsen, D.G. Bohl, E. Paek, E. Dickenson, “Plasma-based water treatment: development of a general mechanistic model to estimate the treatability of different types of contaminants", Accepted JPhysD-110632.R1 (2016).
M. Caso, D.G. Bohl, “Error Reduction in Molecular Tagging Velocimetry Via Image Pre-Processing”, Experiments in Fluids, Vol. 55, DOI: 10.1007/s00348-014-1802-9 (2014).
J.T. Hrynuk, J. Van Luipen, D.G. Bohl, “Flow Visualization of a Vortex Ring Interaction with Permeable Surfaces”, Physics of Fluids, Vol. 24, n 3, DOI: 10.1063/1.3695377, Article number: 037103, 2012.
J.T. Hrynuk, J. Van Luipen, D.G. Bohl, “Flow Visualization of a Vortex Ring Interaction with Permeable Surfaces”, Physics of Fluids, Vol. 24, n 3, DOI: 10.1063/1.3695377, Article number: 037103, 2012.
D.G. Bohl, N. Santitissadeeekorn, A. Mehta and E. Bollt, "Characterization of Mixing Using Experimentally Derived Velocity Fields and Lagrangian Coherent Structures in a Simple Paddle Mixer," Journal of Fluids Engineering, Vol. 133, No. 6, Article nymber: 061202 (2011).
J. Ke and D.G. Bohl, "Effect of Experimental Parameters and Image Noise on the Error Levels in Simultaneous Velocity and Temperature Measurements Using Molecular Tagging Velocimetry/Thermometry (MTV/T)", Experiments in Fluids, Vol. 50, No. 2, pp. 465-478 (2011).
D.G. Bohl and M.M. Koochesfahani, "MTV Measurements of the Vortical Field in the Wake of an Airfoil Oscillating at High Reduced Frequency," Journal of Fluid Mechanics, Vol. 620, pp. 63-88 (2009).
D.G. Bohl, M.M. Koochesfahani, “MTV Measurements of the Vortical Field in the Wake of an Airfoil Oscillating at High Reduced Frequency”, Journal of Fluid Mechanics, Vol. 620, pp. 63-88, 2009.
N. Santitissadeekorn, D.G. Bohl, E. Bollt, “Analysis and Modeling of an Experimental Device by Finite-Time Lyapunov Exponent Method”, Journal of Bifurcation and Chaos, Vol. 19, No. 3, pp. 993–1006, 2009.
N. Santitissadeekorn, D.G. Bohl and E. Bollt, "Analysis and Modeling of an Experimental Device by Finite-Time Lyapunov Exponent Method," Journal of Bifurcation and Chaos, Vol. 19, No. 3 (2009).
D.G. Bohl, R. Lee and E. Palmero, "Break-Up and Performance of Reactive Materials," D.G. Bohl, R. Lee, E. Palmero, "Break-Up and Performance of Reactive Materials", JANNAF Journal, Vol. 1 (May 2008).
D.G. Bohl, "Experimental Investigate of the Fluid Motion in a Batch Mixer Driven by a Flat Plate Impeller," Journal of Fluids Engineering, Vol. 149, No.6, pp.137-146 (2007).
D.G. Bohl and G. Jackson, "Experimental Study of the Spill and Vaporization of a Volatile Liquid," Journal of Hazardous Materials, Vol. 140, No. 1-2, pp. 117-128 (2007).
D.G. Bohl and 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 and 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 and B.J.Olson, "Development of Stereoscopic Molecular Tagging Velocimetry," Experiments in Fluids, Vol. 30, No.3, pp 302-308 (2001).
D.G.Bohl and 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