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Tim Colonius B.S., University of Michigan (Ann Arbor), 1987; M.S. Stanford University, 1988; Ph.D., Stanford University, 1993 1200 East California Boulevard | website
Research Professor Colonius' research efforts are aimed at understanding and reliably computing complex unsteady flow phenomena such as sound generation, coupled fluid dynamic and acoustic resonance, and cavitation. Numerical investigations of unsteady flows can play a key role not only in the development of accurate prediction capabilities, but also in understanding the detailed flow physics and establishing lower-order models of the flow. A major area of interest in this group is the sound generated by turbulent shear flows. Directly computing turbulent mixing layers, jets and their radiated acoustic field from the equations of motion provides a detailed database which may be used to understand the mechanisms of sound generation and validate simplified models for the sources. Efforts are also aimed at understanding and controlling self-sustained oscillations in the flow past an open cavity. Intense pressure fluctuations in open cavities on aircraft cause internal component damage, structural fatigue, and intense noise radiation. Simulations will be used to evaluate and optimize closed-loop feedback control schemes to reduce the pressure fluctuations in the cavity. Cavitation occurs in a wide variety of engineering flows, and the collapse of individual bubbles or clouds of bubbles can lead to very significant sound generation and erosion of nearby solid surfaces. The goal of our research in this area is to develop robust and efficient techniques for computing flows in which the dynamics of cavitation bubbles are strongly coupled to the fluid motion. In addition, work is ongoing to improve numerical methods for computing unsteady flow. Areas of interest include the development and parallel implementation of high-order-accurate methods, artificial boundary conditions, and extension of the vortex particle method to compressible flows.
Selected Publications Model Reduction for Compressible Flows using POD and Galerkin Projection, Rowley, C.W., Colonius, T. and Murray, R.M., Physica D. 189 (1-2): 115-129, Feb. 15, 2004 Modeling Artificial Boundary Conditions for Compressible Flow, Colonius, T, Annu. Rev. Fluid Mech. 36: 315-345, 2004 Inverse-Imaging Method for Detection of a Vortex in a Channel, Suzuki, T. and Colonius, T., AIAA J. 41 (9): 1743-1751 Sep. 2003 A Super-Grid-Scale Model for Simulating Compressible Flow on Unbounded Domains, Colonius T. and Ran, HY, J. Comput. Phys. 182 (1): 191-212, Oct. 10, 2002 An Evaluation of Linear Instability Waves as Sources of Sound in a Supersonic Turbulent Jet, Mohseni, K., Colonius, T. and Freund, J.B., Phys. Fluids 14 (10): 3593-3600, Oct. 2002 A Vortex Particle Method for Two-Dimensional Compressible Flow, Eldredge, J.D., Colonius, T. and Leonard, A, J. Comput. Phys. 179 (2): 371-399, Jul 1, 2002 On Self-Sustained Oscillations in Two-Dimensional Compressible Flow Over Rectangular Cavities, Rowley, C.W., Colonius, T. and Basu, A.J., J. Fluid Mech. 455: 315-346, Mar. 25, 2002 A Numerical Investigation of Unsteady Bubbly Cavitating Nozzle Flows, Preston, A.T., Colonius, T. and Brennen, C.E., Phys. Fluids 14 (1): 300-311, Jan. 2002 |
