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# Analytical solution for wave diffraction around cylinder

Author Affiliations

• 1Dept. of Mathematics, Faculty of Sci. & Tech., Universiti Malaysia Terengganu 21030 Kuala Terengganu, Terengganu Darul Iman, MALAYSIA

Res. J. Recent Sci., Volume 2, Issue (9), Pages 5-10, September,2 (2013)

## Abstract

Waves are one of the energy resources that intensively studying nowadays. The awareness about climate changes, global warming etc makes many researchers interested in developing the new source of the renewable energy by using the ocean waves. The energy from waves is become popular because it is the natural energy and it does not extinct like other sources of energy such as oil. One of the technologies to extract the energy from ocean waves that is becoming popular among the researchers nowadays is oscillating water column (OWC). In this paper, the mild-slope equation is further extended to be applied to the OWC problem. The mild slope equation is a powerful tool to study the phenomenon of combined refraction-diffraction of ocean waves over a mild topography. Therefore, in this paper, we will present the analytical solution for the long waves propagating over a circular hump located at the bottom of an ocean with a hollow circular cylinder floating on the top of the free surface. Then, an example is given to compare our new analytic solution in a special case of the two-layer fluid model, i.e h = 0 with the solution obtained by Mac Camy and Fuchs. To further verify our solution, we have also compared our solution when the hump height, d is small enough with the flat bottom. Then, by using the new solution, we then discuss the effects of the hump dimensions and the hollow cylinder structures on the wave diffraction. Finally, the main findings in this chapter will be briefly summarized at the end of this paper.

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