Free surface wave interaction with an oscillating cylinder

2014-01-01
The numerical solution of the special integral form of two-dimensional continuity and unsteady Navier Stokes equations is used to investigate vortex states of a horizontal cylinder undergoing forced oscillations in free surface water wave. This study aims to examine the consequence of degree of submergence of the cylinder beneath free surface at Froude number 0.4. Calculations are carried out for a single set of oscillation parameters at a Reynolds number of R = 200. Two new locked-on states of vortex formation are observed in the near wake region. The emphasis is on the transition between these states, which is characterized in terms of the lift force on the cylinder and the instantaneous patterns of vortex structures and pressure contours in the near wake.
APPLIED MATHEMATICS LETTERS

Suggestions

Quantitative electrostatic force measurement in AFM
JEFFERY, Steve; Oral, Ahmet; Pethica, John B. (2000-04-02)
We describe a method for measuring forces in the atomic force microscope (AFM), in which a small amplitude oscillation(similar to 1 Angstrom(p-p)) is applied to a stiff(similar to 40 N/m) cantilever below its first resonant frequency, and the force gradient is measured directly as a function of separation. We have used this instrument to measure electrostatic forces by applying an ac voltage between the tip and the sample, and observed a variation in contact potential difference with separation. We also sho...
Free surface flow simulation with application to bluff body flow control
Kocabiyik, S.; Bozkaya, Canan (2015-03-01)
To better understand the interaction of a free surface wave motion with moving bluff bodies, a two-dimensional numerical study of the forced streamwise oscillation of a circular cylinder beneath a free surface is conducted based on a two-fluid model. Computations are carried out at a Reynolds number of R = 200, a fixed displacement amplitude, A = 0.13 and the forcing frequency-to-natural shedding frequency ratios, f/f (0) = 1.5,2.5,3.5. Finite volume discretization of the special integral form of two-dimens...
Streamwise oscillations of a cylinder beneath a free surface: Free surface effects on fluid forces
Kocabiyik, Serpil; Bozkaya, Canan (2015-11-01)
A two-dimensional free surface flow past a circular cylinder forced to perform streamwise oscillations in the presence of an oncoming uniform flow is investigated at a Reynolds number of R=200 and fixed displacement amplitude, A=0.13, for the forcing frequency-to-natural shedding frequency ratios, f/f(0) = 1.5, 2.5, 3.5. The present two-fluid model is based on a velocity-pressure formulation of the two-dimensional continuity and unsteady Navier-Stokes equations. The continuity and Navier-Stokes equations ar...
Spin force and torque in non-relativistic Dirac oscillator on a sphere
Shikakhwa, M. S. (2018-03-30)
The spin force operator on a non-relativistic Dirac oscillator (in the non-relativistic limit the Dirac oscillator is a spin one-half 3D harmonic oscillator with strong spin-orbit interaction) is derived using the Heisenberg equations of motion and is seen to be formally similar to the force by the electromagnetic field on a moving charged particle. When confined to a sphere of radius R, it is shown that the Hamiltonian of this non-relativistic oscillator can be expressed as a mere kinetic energy operator w...
Free surface flow past a circular cylinder under forced rotary oscillations
Kocabıyık, Serpıl; Bozkaya, Canan; Liverman, E. (null; 2014-07-25)
Numerical results of a viscous incompressible two-fluid model with an oscillating cylinder are analyzed. Specifically, two-dimensional flow past a circular cylinder subject to forced rotational oscillations beneath a free surface is considered. Numerical method is based on the finite volume method for solving the two-dimensional continuity and unsteady NavierStokes equations. The numerical simulations are carried out at a Reynolds number of R = 200 and a Froude number F r = 0.2, and the cylinder submergence...
Citation Formats
C. Bozkaya, “Free surface wave interaction with an oscillating cylinder,” APPLIED MATHEMATICS LETTERS, pp. 79–84, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40062.