Surfaces for Drag Reduction

Web Published:

Princeton Docket # 15-3149-1


Researchers at Princeton University, Department of Mechanical and Aerospace Engineering, have developed a method to reduce the drag on solid objects opposed to fluid flow.


Most liquid repellent surfaces are superhydrophobic, which contain pockets of air within surface roughness. Traditional air-water drag reduction surfaces fail under even moderate hydrostatic pressures, upon physical damage, and when using low surface tension liquids such as crude oil. In particular, up to the present time none of the previous surfaces have been successful in reducing drag in high Reynolds number turbulent flows because the trapped gas is metastable. Once the gas pockets are eliminated, the drag reduction feature vanishes. 


This innovation describes a method for drag reduction that relies on a liquid-liquid interface rather than an air-liquid interface. This design allows the surface to be much more robust to external forces and it allows for a surface that can produce significant drag reduction in high stress vehicular and industrial flow environments, such as fluid distribution systems, and vehicular transport. The proposed surface is more robust to damage, lasts longer, and has been shown to reduce drag in turbulent flow conditions where conventional superhydrophobic surfaces failed.


•       Drag reduction

•       Transportation: vehicle surfaces

•       Marine applications

•       Fluid-delivery networks: pipelines


•       Robust to external forces

•       Reduces shear stress in high shear environments

•       Long-lasting


The Faculty Inventor

Howard A. Stone, Donald R. Dixon and Elizabeth W. Dixon Professor in Mechanical and Aerospace Engineering and Chair

Howard Stone is the Donald R. Dixon '69 and Elizabeth W. Dixon Professor in Mechanical and Aerospace Engineering at Princeton University. His research has been concerned with a variety of fundamental problems in fluid motions dominated by viscosity, so-called low Reynolds number flows, and has frequently featured a combination of theory, computer simulation and modeling, and experiments to provide a quantitative understanding of the flow phenomenon under investigation. Prof. Stone is the recipient of the most prestigious fluid mechanics prize, the Batchelor Prize 2008, for the best research in fluid mechanics in the last ten years. He is also a Fellow of the American Academy of Arts and Sciences and is a member of the National Academy of Engineering and the National Academy of Sciences.


Marcus Hultmark, Assistant Professor of Mechanical and Aerospace Engineering


Professor Hultmark received his Ph.D. from Princeton University in 2011 after receiving the Porter Ogden Jacobus Fellowship in 2010 – the highest honor awarded by the graduate school. His research interests include a variety of problems related to turbulent flows, with focus on transport phenomena, such as heat and mass transfer as well as drag reduction. An important part of his research program is development and evaluation of new sensing techniques to investigate these phenomena with high accuracy.


Alexander Smits, Eugene Higgins Professor of Mechanical and Aerospace Engineering


Alexander Smits’s research interests are centered on fundamental, experimental research in turbulence and fluid mechanics. Particular aspects include Reynolds numbers scaling of turbulent flows, the effects of roughness; bio-inspired propulsion; drag reduction using liquid-infused porous surfaces; the behavior of turbulent flows at supersonic and hypersonic speeds; shock-wave/turbulent boundary layer interactions; vertical axis wind turbine aerodynamics; sports ball aerodynamics, and the development of new and improved measurement techniques.

Professor Smits is the author and co-author of several books in areas of turbulent flow and fluid mechanics and more than 200 peer-reviewed journal articles. He is the recipient of numerous awards including Aerodynamic Measurement Technology Award from the American Institute of Aeronautics and Astronautics (AIAA) in 2014. He was the Chair of the Division of Fluid Dynamics of the American Physical Society in 2007-2008.  He is a member of the National Academy of Engineering, and the Editor-in-Chief of the AIAA Journal. He is also an Associate Editor of the Journal of Turbulence and he is on the Editorial Board of the Journal of Sports Engineering and Technology.


Intellectual Property & Development status

Patent protection is pending.

Princeton is currently seeking commercial partners for the further development and commercialization of this opportunity.




Michael R. Tyerech

Princeton University Office of Technology Licensing • (609) 258-6762•

Xin (Shane) Peng

Princeton University Office of Technology Licensing • (609) 258-5579•




Patent Information:
For Information, Contact:
Chris Wright
Licensing Associate
Princeton University
Marcus Hultmark
Alexander Smits
Howard Stone
Matthew Fu
Brian Rosenberg
Jason Wexler
Ian Jacobi