Dynamics of turbulent Taylor-Couette flow via exact Navier-Stokes solutions - Topic 1.1.2
Abstract
This proposal seeks to establish that the concept of ""Exact Coherent Structures"" is a viable description of the dynamics of unsteady turbulent flows. ECS represent solutions of the Navier-Stokes equations formulated using concepts from dynamics of complex systems. Specific objectives include determination of the dominant ECS of moderately unsteady and turbulent flow fields in a canonical flow (Taylor-Couette flow) as well as the computation of the low-dimensional dynamical connections between the dominant ECS and the optimal perturbations responsible for changing from one ECS to another. This effort represents truly basic research and brings to bear theoretical, numerical and experimental tools on a perennially difficult problem. The plans include a systematic analytical and numerical approach to compute an experimentally realizable turbulent flow so that the results can be verified by experimental testing. The Taylor-Couette flow (flow between rotating concentric cylinders) is an appropriate model system to examine the viability of this theoretical approach due to the well-posedness of the boundary conditions, the ease with which high-resolution measurements can be conducted and the correct balance of simplification and complexity. An experimental facility is already in place at the research institution and the academic partnerships are in place to allow the experimental verification to be conducted. While Taylor-Couette flow represents a simplified canonical flow, it has sufficient complexity and manifests a number of flow instabilities that the ECS description may be capable of identifying. It is anticipated that, if successful, an increase in the understanding of the underlying structures in turbulent flows will lead to new thinking about more complex flows with complex geometries. A major outcome of this effort is not only the identification of the ECS, but also the perturbations required to move from one ECS configuration to another, which has implications into direct flow control through manipulation of turbulent states (rather than the typical exploitation of large-scale flow instabilities).
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 14, 2016
- Source ID
- W911NF1510471
Entities
People
- Roman O Grigoriev
Organizations
- Army Contracting Command
- Georgia Tech Research Corporation
- United States Army