CONCLUSIONS
In this paper, the shape of a new under water glider was designed with the Blended-Wing-Body (BWB) configuration, and the parametric geometric model of this underwater glider has been built with 10 design variables. The hydrodynamic perform-ance of the BWB underwater glider was evaluated using a Navier-Stokes code. The Efficient Global Optimization (EGO) was used to solve the hydrodynamic design optimization which has expensive black-box functions. By summarizing the results of this study, we conclude as follows.
1) The hydrodynamic performance of the BWB underwater glider is obviously better than that of conventional under water glider such as Slocum Battery/Thermal glider, the Stingray (or Manta) glider and the Sea-glider.
2) The lift to drag ratio of initial design has been enhanced by 7%in the EGO process.
3) The sensitivity of the lift to drag ratio to each of the design variables was analysed, and according to the result, it was found that the relative thickness of airfoil and sharpness of the nose are important factors affecting the hydrodynamic performance.
In this paper, the BWB underwater glider has been designed without considering the control surfaces. Actually, the vertical control surfaces (winglets) effectively reduce the induced drag. The design and optimization of the winglets will be taken into account in the future research.