Calculation of Hydrodynamics Resistance Coefficient of Diver by CFD Method

Document Type : Original Article


1 Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran.

2 Department of Physical Education and Sport Sciences, Kharazmi University, Tehran, Iran.

3 Department of Civil Engineering, Shahrood University of Technology, Shahrood, Iran.



The purpose of the present study is calculation of the resistance and resistance coefficient of a diver at underwater swimming. One of the results of this article is useful for designing different types of thrusters. This study uses a computational fluid dynamics methodology. SST k-omega turbulent model is implemented in the Star-CCM+ application and is applied to the flow around a three-dimensional model of an adult human bare hull. Three common swimming positions are investigated in an adult swimmer: a ventral position with the arms extended at the front, a ventral position with the arms placed alongside the trunk and a ventral position with one arm extended at the front and another arm placed alongside the trunk. The simulations are applied to flow velocities between 0.5 and 2.25m/s with increasing step of 0.25m/s, which are typical speed of swimmers. According to the resistance coefficient vs Reynolds number diagrams, submerged diving with two hands alongside the trunk is the best way of diving with lower resistance.


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