Physical modeling of solid spheres’ motion under solitary wave attack

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2020-8
Göral, Koray Deniz
In this study, the motion and collision of the spheres under the solitary wave attack is studied. The physical experiments were carried out in a wave channel at Middle East Technical University Ocean Engineering Research Center Laboratory that has 26 m length and 0.9 m width with the slopes of 1:20 for breaking solitary wave conditions and 1:4.5 for non-breaking solitary wave conditions that followed by a horizontal area. Two different colored spherical homogeneous balls with a diameter of 10 cm and 2712 kg/m3 in density are used for the single sphere and double sphere experiments. The motion of a single sphere and the motion and the collision of the double sphere cases were examined with the changing permeability of the bottom as impermeable and porous, water levels and type of solitary waves as non-breaking and breaking. Therefore, 4 different experimental configurations were constructed and 16 different cases were performed in the present study. Each case was repeated 21 times to reduce the bias on the results. The paths of the spheres were tracked with the homemade image processing code based on color detection algorithm. The dimensionless trajectories and the dimensionless velocities are given for each case. It is seen from the results that different permeabilities of the bottom, water levels and types of the solitary waves are significantly affecting the behavior of the motion of vi the spheres. Also, the collision of the spheres is considerably changing the behavior of the motion of the spheres, especially when they did not collide in the halfsubmerged condition effected with the breaking solitary waves. This study presents a unique dataset that shows the fundamentals of the motion of the spheres under a solitary wave attack. Besides, the mentioned dataset can be used for the calibration and validation purposes of the newly developed CFD-DEM solvers.

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Citation Formats
K. D. Göral, “Physical modeling of solid spheres’ motion under solitary wave attack,” M.S. - Master of Science, Middle East Technical University, 2020.