Martin Maxey

Professor:
Applied Mathematics
Phone: +1 401 863 1482
Phone 2: +1 401 863 1414
Martin_MaxeyBrown.EDU

Ph.D., University of Cambridge, 1979

Professor Maxey’s research in fluid dynamics is focused on dispersed two-phase flows such as suspensions of particles in liquids. Current applications of interest include self-assembly in micro-scale flows, swimming of single cell organisms and blood flow. Other research areas include turbulent flows and mixing with applications to physical and geophysical systems.

BIOGRAPHY

Professor Maxey completed his undergraduate and graduate education at the University of Cambridge and received his Ph.D. in Applied Mathematics and Theoretical Physics in 1979. In 1977, he was a pre-doctoral research fellow in the Geophysical Fluid Dynamics Summer Program at Woods Hole Oceanographic Institute. He held a post-doctoral position in the Department of Mechanics and Materials Science at the Johns Hopkins University and subsequently was a lecturer in the Department of Chemical Engineering at Johns Hopkins. He joined the Division of Applied Mathematics at Brown University in 1982. He is presently Professor of Applied Mathematics and Engineering and since 1991 has served as Director of the Center for Fluid Mechanics, Turbulence and Computation. He is a member of the editorial board for the International Journal of Multiphase Flow and is a fellow of the American Physical Society.

RESEARCH INTERESTS

Recent research projects include methods for turbulent drag reduction, the manipulation of small paramagnetic particles with magnetic fields to form self-assembled structures in a suspension, active suspensions of microorganisms or artificial swimmers, and problems relating to the transport and coagulation of platelets in blood flow. In these projects, we have developed direct numerical simulations and theoretical models that characterize the microstructure help understand the overall processes.

In a DARPA-sponsored project aimed at reducing drag on ship hulls, we have been studying the dynamics of micro-bubbles injected into turbulent shear flows and how these may alter the near-wall flow. The technique of micro-bubble injection is known to work in laboratory experiments but there has been little theory as to how drag reduction is achieved or how it might be scaled. Previously we had provided the first demonstration of drag reduction through a direct numerical simulation. We have developed new simulations for spatially-developing channel flows that now provide a direct basis for comparison with experiments. Our simulations have further identified bubble-bubble contacts as an important factor in bubble dispersion, which in turn controls the persistence of drag reduction. Drag reduction may be enhanced by the presence of a gas film at the walls. Papers on this work were presented at the 2nd Int. Symp. Seawater Drag Reduction, held in Busan, S.Korea in 2005.

With NSF support, we are studying the dynamics of paramagnetic beads in suspensions. These beads (~ 1 micron in size) are commonly used in biomedical testing and can be treated to respond to biochemical agents. When in suspension they can be manipulated by magnetic fields to form self-assembled structures such as chains that can be used in micro-devices to create optical filters, or as flow pumps and actuators. They can be used also to produce mixing in a fluid, or for manipulating individual cells in biomedical applications. We have developed new simulation methods to accurately predict the interactions between magnetic beads. We have demonstrated the strong role of 3D-geometry of the flow device on the chains that form, and verified these results against available experiments. We are presently investigating the effects of unsteady or rotating magnetic fields. Surface physics and short-range interactions play a role too. We have been using molecular dynamics (MD) simulations and the dissipative particle dynamics (DPD) to investigate the link between these nano-scale and mescopic features to link them to larger scale simulations.

In a new project, we are studying the dynamics of platelet coagulation in blood flow in both large blood vessels and in small capillaries.

COLLABORATORS

George Karniadakis

Peter Richardson

Prof. Eric Climent, Laboratoire de Genie

Awards

Fellow, American Physical Society, elected September 2005

Japan Society for the Promotion of Science, Invited Research Fellow, 1997

Affiliations

American Geophysical Union

American Physical Society

American Society of Mechanical Engineers

Sigma Xi

Society for Industrial and Applied Mathematics (SIAM)

Society of Rheology

Editorial Board – International Journal of Multiphase Flow

Funded Research

Current Awards

DARPA, ATO – Friction Drag Technologies Program, subcontract through ARL – Penn State Univ., November 2003 – April 2006, P.I. (co-P.I. G. Karniadakis) at Brown University. Multiscale physical modeling for micro-bubble drag reduction at high Reynolds numbers. (RFP 04-15)

National Science Foundation – CTS - Fluid, Particulate and Hydraulic Systems Program, Jan 2004 – Dec 2006, P.I. (co-P.I. G. Karniadakis) Simulation of Magnetorheological Fluids: Microdevices and Self-Assembled Structures.

National Science Foundation – DMS - Multiscale Modeling: BBB, Sep 2005 – Aug 2006, Co-P.I. (P.I. G.E. Karniadakis and co-P.I. P.D. Richardson) A Stochastic Molecular Dynamics Method for Multiscale Modeling of Blood Platelet Phenomena. (Award DMS-0506312)

Completed Awards

National Science Foundation - ATM8310136, Nov. 1984 - Feb. 1988. Study of the fallout and dispersion of particles in turbulence and random fields.

National Air and Space Administration, with L.Sirovich, 1986-1987. Problems in fluid dynamics.

DARPA, University Research Initiative, L. Sirovich-Director, Oct. 1986 - March 1992. Analysis, Prediction and Control of Turbulent Flows.

DoD, DURIP equipment grant for computer systems, (with L. Sirovich, E. Meiburg). Oct. 1988 - Sept. 1989.

Office of Naval Research - ARI on Dynamics of Bubbly Flows, Nov. 1990-Oct. 1993. The dynamics of bubbly flows and the modification of turbulence by microbubbles.

National Science Foundation - DMS 9205227, Sept. 1992-Feb. 1994, Principal Investigator (Co-P.I.'s, C. Jones, D. McClure, L. Sirovich). Mathematical Sciences Computing Research Environments.

Office of Naval Research - ARI on Dynamics of Bubbly Flows, Nov. 1993-April 1996. The dynamics of bubbly flows and the modification of turbulence by microbubbles.

National Science Foundation - STI-9413819, Academic Research Infrastructure Program. Co-P.I. (P.I. G. Karniadakis), Oct. 1994-Sept. 1995. Acquisition of a parallel supercomputer.

National Science Foundation - CTS9424169 - Fluid, Particulate and Hydraulic Systems Program, May 1995-April 1998, Interactions of finite-sized particles and turbulence in dispersed two-phase flow.

National Science Foundation - DMS9628601, (with G. Karniadakis, D. Gottlieb, C. Jones and D. McClure), Aug. 1996-July 1997, Mathematical Sciences Computing Research Environments.

National Science Foundation - CTS9619232 - Fluid, Particulate and Hydraulic Systems Program, Co-P.I. (P.I. G. Karniadakis), Sept. 1997 - Aug. 1998. A new model for turbulence based on the hydrodynamics - electromagnetism analogy.

National Center for Microgravity Research, USRA 4500-03, Sept. 1998- Oct. 1999. Initial investigation of particle interactions and dispersed two-phase flow under low gravity conditions.

DARPA, ATO – Friction Drag Technologies Program, MDA972-01-C-0024, March 2001 – September 2003. P.I., with G. Karniadakis and B. Caswell co-PI's at Brown University. Microbubble and microbubble/polymer turbulent drag reduction.

Web Links

Martin Maxey, Professor of Applied Mathematics and Engineering

Also please visit the Center for Fluid Mechanics website.