Rene Chevray

Rene Chevray is a Professor of Mechanical Engineering at Columbia University, and the Director of the Turbulence Research Laboratory. He received his Ph.D. from the University of Iowa in 1967 and his D.Sc. from the Claude Bernard University of Lyon in 1978. Professor Chevray can be contacted at:

• Address: 220 S.W Mudd Building Department of Mechanical Engineering 500 W. 120th St. New York, N.Y. 10027
• Tel: Office (212) 854-2970 Laboratory (212) 854-2922
• Fax: (212) 854-3304
• Email: [email protected]

• Dynamical Systems in Fluid Mechanics and Chaotic Advection: A novel method of fluid mixing "chaotic advection" is studied from a fundamental point of view. Applications to systems which cannot sustain high strain rates are studied; in particular, this method is presently used to separate fetal erythrocytes from maternal blood. It is also used to separate particles with only slight variations in size or density.
• Development of a new model of Turbulence. An apparent body force hypothesis is put forward for turbulent flows. Important characteristics of this model include accurate prediction of complicated turbulent shear flows, in particular for zones of null velocity gradients where the shear stress is finite. A basic turbulent situation, that of a distorted duct in which a grid generated turbulence is subjected to a pure plane strain is studied experimentally to study this new model. This reorientation of the principal axes provides an example of the evolution of the principal axes of the Reynold's stress tensor in a shear flow.
• Coating processes with Viscoelastic Liquids: We are studying, numerically and experimentally, flows of small scale laminar free-surface flows in order to be able to deposit one or several liquid films on a moving substrate. These flows invariably involve non-Newtonian viscoelastic fluids whose behavior is little understood especially in the high Weisenberg number regime corresponding to the elastic behavior used in coating operations.
• Drag Reduction by Polymeric Fluid: The well-known phenomenon of drag reduction by long chain molecules introduced in a turbulent flow is still not understood. In an effort to understand this mechanism, we are studying flows of polymeric fluids in a free jet configuration where the total absence of walls might reveal details of the fine structure of turbulence which is quite different with and without polymers.

Recent Publications

Full-Length Papers

1. R. Chevray and J. Mathieu, Topics in Fluid Mechanics, Cambridge University Press, graduate text- book, 1993.
2. R. Chevray and P. Dutta, "Fluid Mixing by Chaotic Advection," Proceedings, First ISHMT-ASME Heat and Mass Transfer Conference, Sukhatone et al., Ed., Vadams Books International, 1994.
3. P. Dutta and R. Chevray, "Role of Transient Velocities and Diffusion of Chaotic Advection in an Eccentric Annulus," Proceedings, Fifth Asian Congress of Fluid Mechanics, Daejon, Korea, June 1992.
4. P. Dutta and R. Chevray, "Effects of Diffusion on Chaotic Advection in Stokes Flow," The Physics of Fluids A, Vol. 3, 1991, pp. 1440.
5. R. Chevray, "Fractals," Yearbook of Science and Technology, McGraw-Hill Encyclopedia of Science and Technology, 1991.
6. E. Panides and R. Chevray, "Vortex Dynamic in a Plane, Moderate-Reynolds-Number Shear Layer," J. Fluid Mech., Vol. 214, 1990, pp. 411.
7. R. Chevray, "Chaos and the Onset of Turbulence," Chapter 5, Advances in Turbulence, W. K. George and R. Arndt, Editors, Hemisphere, 1989, pp. 127-158.
8. R. Chevray, "Chaotic Advection in a Shear Layer," American Physical Society, Bulletin, 34, 1989, p. 1143.
9. S. Iida and R. Chevray, "Solving Laminar Boundary Layer Equations," Chapter 4, Encyclopedia of Fluid Mechanics, N. P. Cheremisinoff, Editor, Golf, 1989, pp. 83-110.
10. R. Chevray, K. Ogawara, and S. Iida, "General Aspects of Chaotic Phenomena", J. Japan Society of Mechanical Engineers, Vol. 91, 1989, pp. 1129-1134.
11. P. Dutta and R. Chevray, "Inertial Effects in Chaotic Mixing with Diffusion", J. Fluid Mech., Vol. 285, 1, 1995.