Numerical Simulation of Strong Turbulence over Water Waves
Mississippi State University
Haupt, Thomas Aleksander
Sajjadi, Shahrdad G.
Date of Degree
Graduate Thesis - Open Access
Computational Engineering (program)
Master of Science
James Worth Bagley College of Engineering
Recently a viscoelastic turbulence closure model, based on that of Townsend (1976), for wind-wave interactions by turbulent wind has been proposed by Sajjadi (2001). In that work, the governing equations of mean and turbulence were linearized and solved analytically using an asymptotic method. In this work the equations derived by Sajjadi were solved numerically for the cases of strong turbulence due to wind over surface of a monochromatic water wave. Vortex shedding has been observed at high wind velocities. Also, a layer of vortices separating the main flow of wind from the water surface was observed from the results for high velocities of wind. A finite difference scheme was devised which is second order accurate. The results were compared with another scheme based on the method of superposition coupled with orthonormalization by Scott andWatts (1977). The two schemes agree reasonably well for high velocities while they differ for low velocities. Two test cases were implemented to test the finite difference scheme. The tests show that the finite difference scheme predicts accurate solutions for inhomogeneous equations, while it fails to capture the accurate solution if a non trivial solution exists for homogeneous equations. This is attributed as the reason for the difference in the results.
Kakollu, Satyanarayana, "Numerical Simulation of Strong Turbulence over Water Waves" (2003). Theses and Dissertations. 3329.