Open Collections

Hydrodynamic coefficients of compound circular cylinders in surge motion

University of British Columbia

The hydrodynamic coefficients, that is the added mass and damping coefficients, are determined experimentally for compound circular cylinders in surge motion. The surge force induced by forced harmonic oscillation of cylinder models is measured. In addition the induced wave height in the flow field is also measured. The effect of varying the displacement amplitude, the frequency of oscillation and the cylinder draft are investigated for single, double and triple cylinder models. The results are compared to the theoretical predictions of the Matching Technique (MT) and the Boundary Element Method (BEM). The Matching Technique formulation uses continuity of pressures and velocities between adjacent regions in the flow field to solve for the velocity potentials and hence to determine the hydrodynamic coefficients of the cylinder models. Application of the Boundary Element Method is simplified by the axisymmetry of the problem. In this method a control volume is defined and discretized into ring shaped elements. The potential within each element can then be solved simultaneously using the boundary conditions. In addition experiments were conducted to measure the wave induced exciting force on the cylinder models and the results of these experiments were compared with the theoretical predictions of the Boundary Element Method.

Text

2010-07-10

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.

http://hdl.handle.net/2429/26290

Mechanical Engineering

University of British Columbia

Graduate