Research On The Channel Width Based On The Maneuvering Simulating Test In Shipu Port

Xiangshan Peninsula where Shipu port area of Ningbo-Zhoushan port is located,has always been a gateway of Zhejiang Province,while Shipu bay in the south of the peninsula which has an advantageous geographical location,deep water,and a glorious exploitation history,hasn't been exploited well as for the port and nor made great progress in local industry due to the restriction of the channel.To adapt to the construction and development of the port,it is planned to build channels for 10,000 dwt ships above.However,the complexities of natural conditions,varieties of wind and current,and especially the effect of current,together increase difficulties to the designing of the channel.The method for calculating the width of the channel is given in the Overall Design Code for Sea Ports(JTS 165-2013)of China.In this method,the channel widths are all calculated under the conditions that crosswind level is less than or equal to a moderate gale,all currents are regarded as crosscurrents,the current velocity is between 0.10 m/s?1.00 m/s,and differential pressures of wind and current are valued respectively from 3°to 14°according to the degree of the impact that current velocity exerts on ship steering.As parameters in the formula have shown,the main natural conditions which influence channel width are wind and current.Since wind and current exert dynamic influences on the navigation,different channel widths are needed under different combinations of wind and current.Particularly to the navigable waters where the tidal currents are complex,the safe width for ship navigation may be larger than the calculated value.Therefore,the experts hold different points of views on the value according to the present Overall Design Code for Sea Ports(JTS 165-2013)of China.The main channel width in Shipu port was get by ship simulation test in this paper.Due to the complexity of the waters,the measured data couldn't stand for the feature of the whole tidal current.In this paper,MIKE software was used to simulate the current data of any position in the whole channel.Moreover,the environment simulation considering actual measurements of wind and current data was carried out,and the mathematic model of ship movement simulation was build.In accordance with the channel environment in Shipu port,10000 dwt bulk cargo ship was chosen as the representative ship type,which could reflect the local water area to the greatest extent.Many groups of experiments were conducted using the method of ship simulation experiment,and the track-width of ship in this water area was gotten.In terms of the surplus width between the ship and the edge of the channel bottom given by the Overall Design Code for Sea Ports(JTS 165-2013)of China,the channel width of the main channel in the complex waters in the Shipu port area of Zhoushan port was calculated.By verifying,MIKE software can simulate local tidal current environment better and improve the accuracy of test results.According to the test results,as the complexity of wind and current condition and the design width of new channel,it is not safe to limit the navigation speed no more than 6kn.And because of the complex waters of inner passage and gate section,the channel width should be widen to that of the test.