چکیده
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In recent years, marine transportation as well as land and air transportation has become in the centre of attention.
There has been an attempt to reduce the drag exerted on vessels by various methods, such as rough surfaces and
base bleed. Study of the high-speed seawater animals like sharks and dolphins has triggered the use of riblets
on the hull of marine vessels. The use of riblet is easy among various methods of skin friction drag reduction.
For this reason, there is an interest for construction and optimization of riblet as an efficient and economical
way. In this research, the shark’s skin was modeled for the first time in ANSYS CFX using Computational Fluid
Dynamics, through analyzing the effects of riblet on a submerged flat plate. Different types of riblet based on
height and space between micro channels were studied, and then a comparison between a riblet-covered plate
and a smooth plate in various velocities were performed. It was found that by selecting the most appropriate
type of riblet, 11 % drag reduction can be attained. Then, by comparing different types of riblets, the best type
for drag reduction was selected. Furthermore, the obtained results were compared with the available
experimental data.
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