Simulation Calculation Of Maneuverability Of Small Scale Ship Model Of Three Gorges Project

The three gorges construction has great social and economic benefits. The buildingof three gorges project can extended the reaches of Yangtze river, the benefits ofnavigation, flood control, power generation, navigation and other comprehensiveefficiency have significantly improved. At the same time the Yangtze river was a typicallimit waterway and the navigation control problem became more complicated for theconditions of bending, narrow, shallow and rapids of channel, with the addition of thephenomenon of worsening conditions caused by the frequent dense bridges. Soguarantee the safety of the ship navigation of inland channel became most important.Were manipulative ship must have the capability of maintaining the movementdirection when sailing, changing the direction when swerving and halting when braking.Manipulation includes four aspects which are the stability of shipping-direction, theability of ships turning, the ability of turning head and the ability of braking.Manipulation has also related to the six elements on which are the rudder, the ship, theanchor, the cables, the wind and the water. In the design and operation of ship, it isusually considering the above six factors. The traditional design gets the parameters ofthe ship using the test data of ship model and simulating with the empirical formula. Butthis method is less used because the considering factors are so idealized and the testenvironment is too strict. Therefore, the method according the experimental results ofthe ship or ship mode to identify the hydrodynamic derivatives and thoroughly study onthe handling performance has been widely adopted.The manipulation is usually described by index the K, T. T is stood for the abilityships turning. T is stood for the ability of the rapid response ship and the headingstability of ship. The index of K,T is obtained using the method of one order K, Tequation put forward by Ye Ben. The index K,T is relate to the inertia, rotary dampingand the rotary torque of the rudder. K means per rotary torque divide per rotary dampingof rotary angular velocity. T means the inertia of ship divide per rotary damping ofrotary angular velocity. If per rotary damping of rotary angular velocity increased, bothK and Twill be decreased that is the ability of ship turning decreased and theshipping-direction stability strengthened. If don’t change the damping conditions, onlyincrease the rudder effect and rotary torque, the ability of ship will be improvedeffectively. Generally speaking, were manipulative ship should have a larger K andsmaller T.All theory had shortage. The index K, T obtained from test existed deviation to thereal ship because of the influence of ship model scale and the limit of test conditions.This paper obtained the index K, T another perspective using theorem of momentumtheorem and simplifying the process. Through the hydrodynamic model and electing themain influence factors affecting the ship maneuverability: the proportion of the loadresistance, rudder angle and velocity and then using DPS uniform design and designing20test plan and generating into the simplified model we could got the index K, T. Thenobtained the best load combination to guide the ship design and operation through finding out all kinds of combination and using MATLAB software to analysis therelationship between the various factors and the interaction on the ship maneuverability.