Numerical Study of Attack’s Angle Effect on Drag Coefficient of AUV Hull Design

Aymen Mohamed¹, Hedi Kchaou¹, Mohamed Salah Abid¹ and Zied Driss^1,

¹Laboratory of Electro-Mechanic Systems (LASEM), National School of Engineers of Sfax (ENIS), University of Sfax, B.P. 1173, Road Soukra km 3.5, 3038 Sfax, Tunisia

Cite this paper:
Aymen Mohamed, Hedi Kchaou, Mohamed Salah Abid and Zied Driss. Numerical Study of Attack’s Angle Effect on Drag Coefficient of AUV Hull Design. American Journal of Mechanical Engineering. 2017; 5(1):8-13. doi: 10.12691/ajme-5-1-2

Abstract

In the present paper, CFD investigation is performed in order to analyze the effect of angle of attack and strut arrangement within towing tank facility on prediction of the hydrodynamic drag of an autonomous underwater vehicle. Single and two phase calculations basing on Reynolds Averaged Navier–Stokes (RANS) equations were solved using ANSYS FLUENT in order to analyze the effect of free surface on flow features. Therefore, the results were compared with experimental ones provided from a captive model in towing tank tests. The study is accomplished at the depth of 4 of the AUV diameter over various angles of attack from 0° to 15° and different velocity ranging from 0.4m/s to 1.4 m/s. The integration of strut arrangement in CFD analysis shows a significant effect on the hydrodynamic characterization of the hull especially with high incidence. Also, the sensitivity of the free surface to aft body deviation of the AUV has relatively affected the measurement of drag forces.

Keywords:
AUV CFD drag aft body flow separation wake

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