INVESTIGATION OF HYDRODYNAMIC DRAG IN A SWIMMING SQUID

Abstract

In this study, hydrodynamic drag on an adult squid was investigated during its fast swimming phase. Numerical model has been generated from a real squid's computer tomography images. It has been documented that squids can typically swim at velocities from 3.21 m/s to 9.23 m/s under the water. Therefore, by considering the flow on squid's surface and behind the squid, variation of drag coefficients (at these velocities) has been studied for the squid having about 7.58 fineness ratio. It has been noted that streamlined shape of the squid affects drag force associated with total wetted surface area and flow separation; more specifically, streamlined shape both helps to have delayed flow separation and in return to have lower drag coefficient.

Keywords

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INVESTIGATION OF HYDRODYNAMIC DRAG IN A SWIMMING SQUID

Abstract

In this study, hydrodynamic drag on an adult squid was investigated during its fast swimming phase. Numerical model has been generated from a real squid’s computer tomography images. It has been documented that squids can typically swim at velocities from 3.21 m/s to 9.23 m/s under the water. Therefore, by considering the flow on squid’s surface and behind the squid, variation of drag coefficients (at these velocities) has been studied for the squid having about 7.58 fineness ratio. It has been noted that streamlined shape of the squid affects drag force associated with total wetted surface area and flow separation; more specifically, streamlined shape both helps to have delayed flow separation and in return to have lower drag coefficient

Keywords

• Hydrodynamic Drag
• Swimming
• Fineness Ratio
• Squids

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