Analysis On Fast Performance Of Catamaran With SSB

Due to good living conditions,spacious deck area,excellent stability and maneuverability,catamarans are widely used in civil and military fields.But in storm,it's easy to produce pitching and rolling coupled motion which can lead to a great impact on comfort.As an anti-roll possessed,SSB(semi submerged bow)can effectively reduce movement in the storm but it may inevitably cause an increase in resistance.However a rational design will avoid such drawbacks.Straight-wing propeller,also called cycloidal propulsion,has the characteristics of good maneuverability,high efficiency,strong wind resistance and fast response which can greatly improve the propulsion performance of catamaran.In this article,CFD method will be used to investigate the fast performance of a catamaran with SSB.The purpose is to improve its resistance and propulsion performance.For resistance,commercial CFD software CFX has been used to discuss the main factors affecting the CFD calculations.A numerical program suitable for catamaran was given and it was compared with experimental data to verify the feasibility and applicability.Based on this,the impact of SSB on catamaran's flow field was analyzed,then it generated five ship type schemes and the optimal ship line was chosen.Finally,the effect of demi-hull space on the resistance of catamaran was analyzed and the best demi-hull space was confirmed.For propulsion,sliding mesh technology and dynamic mesh technology was used on the simulation of cycliodal propulsion open water performance.The flow field and mechanical characteristics on the blades was analyzed and the effect of eccentricity on the performance was also studied.On the basis of the open water calculation,self-propulsion test was simulated and the complex flow field under the condition of the ship and propeller interference was studied.Then through analysis of CFD results,self-propulsion factor was confirmed.