Wave diffraction from a truncated cylinder in front of a vertical wall

• Present an analytical model for wave diffraction problem of a cylinder near a wall.
• Validate the model by the comparison of present results with numerical ones.
• Conduct a parametric study on wave run-up and wave excitation forces.
• Provide an efficient method for wave diffraction problem of a cylinder near a wall.

This paper presents an analytical model to predict the three-dimensional wave diffraction of a floating cylinder located in front of a vertical wall at a finite water depth. The model is potentially used to analyze the hydrodynamic behavior of a floating wave energy device close to a steep shore. The model is based on a linearized velocity potential theory and the image theory. The wave diffraction problem is transformed into the problem of diffraction of bi-directional incident waves from two cylinders. Expressions for velocity potential are obtained by the method of separation of variables, in which unknown coefficients are determined by using the eigen-function expansion matching method. Wave elevations and wave excitation forces are calculated directly from the incident and diffracted potentials. The model is validated by comparison of the present results with the numerical ones, and there is a good agreement. The effect of wave incident angle, distance between a cylinder and a vertical wall, cylinder draft and water depth on wave run-up and wave forces is then explored.