CAREER: Interaction of Turbulence with Flexible Surfaces: Coherent Structures and Near-Wall Dynamics

Arizona State University, Scottsdale AZ

Investigators

Abstract

The project will investigate the interactions between the flexible surfaces and turbulent flows. The analysis will be based on the combination of computational fluid dynamics simulations and theory. Surfaces that deform under the influence of fluid forces occur in many practical situations, such as vibrations of aircraft wings, human blood vessels, and compliant coatings. The goal of this project is to develop new theories that help explain how these interactions will change the structure of the flow. Simple demonstrations of the fluid-structure interactions in an everyday life will be designed for the outreach activities targeted to females and minorities conducted in collaboration with the university office of education. The focus of the current project is on investigation of the mechanisms involved with the interaction between the flexible surfaces and the near-wall turbulence. Particular emphasis is on understanding of 1) how passive and active wall motions alter the near-wall turbulence cycle, 2) whether and why these alterations lead to a turbulence reduction, and 3) what factors are responsible for changing the mode of interaction. A comparison between the isotropic and anisotropic wall motions will be made to investigate the potential differences of the influence of these motions on the near-wall turbulence cycle. The above goals will be accomplished via a combination of high-fidelity Direct Numerical Simulations (DNS) of a coupled fluid-structure interaction problem, and a suite of analysis tools, including a resolvent analysis, and a linear stochastic estimation approach. Resolvent analysis will provide a-priori and a-posteriori estimates of the effect of certain flow and material parameters on a likelihood of achieving a desired mode of interaction. The educational objectives of the current project are devoted to attraction and retention of female researchers to the field of engineering, accomplished via local outreach activities, as well as a development of interactive fluid flow visualizations for the Internet and iPhone applications, targeted to elementary and middle school children. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.