Research On The Oil Consumption Response To Resistance Reducing Optimization Of The Ship With Wind Load

As the people’s attention focus on the marine economy and environment,more and more attention has been paid to the level of the ship’s fuel consumption by the ship owners.And the ship’s fuel consumption is directly related to the resistance which could be divided into water resistance and wind resistance depending on the different fluid medium.Water resistance is the main component of the ship’s resistance for the main stream merchant ship,therefore in a long period of time,the research of the ship’s resistance mainly focus on the water resistance of the ship.However,as for the deepening of energy conservation and emissions reduction,wind resistance of the ship has become a hot research topic.So it is of great theory and practical significance for the study of wind resistance whether from the point of view of the navigation safety or the energy efficiency improvements.In this thesis,based on the calculation of ship’s wind load in the empirical formula and the CFD method,the oil consumption simulation model is established and the test of actual ship data acquisition is carried out,then,the research on the wind load effects on the fuel consumption of the ship is made to quantify the influence of wind resistance for the ship resistance and fuel consumption,while optimizing the configuration of the ship superstructure,reducing the wind resistance of the ship.The main research work of this thesis is as follows:(1)The calculation of the wind load of the ship is studied.The wind load coefficients in different directions are calculated by the use of Isherwood、Fujiwara and Blendermann method which based on the wind tunnel tast and by the use of FLUENT software,and the calculated results were compared and analyzed.The result shows that the numerical calculations agree with Blendermann method very well in the inland river cruise wind load calculation,and Blendermann method has a higher precision in the calculation of wind load on inland cruise ship,and the method of numerical computation that adopted in this thesis could accurately calculate the wind load of the inland cruise ship.(2)The influence of wind on ship resistance and fuel consumption are studied.Based on the analysis of the data requirements of the inland cruise ship fuel consumption,a data acquisition system was desighed and built,and a lot of navigation environment and fuel consumption data were obtained,then a simulation model of the fuel consumption was established with the deeply explore of the ship fuel consumption mechanism and the working characteristics of ship-propellerengine,in which Blendermann method was used for wind load simulation model.Afterwards,by use of the data that obtained by the real ship and the simulation model,the effect of wind resistance on the ship’s total resistance and fuel consumption was analyzed under different wind speed and direction.The result shows that,the value of the wind speed has a significant impact on the total resistance and fuel consumption of the ship,and the influence of wind direction on the resistance and fuel consumption should not be ignored.(3)The wind resistance-reducing optimization of the ship is studied.Based on the analysis of ship superstructure pressure contours and flow field information and combined with the actual situation of the ship,three kinds of Drag reduction and optimization scheme are proposed and the wind load of the schemes are calculated by use of FLUENT suftware,from which the best configuration was selected.The result shows that,through the streamlined design at the superstructure corner,the three resistance-reducing optimization schemes have reached the resistance reduction and oil-saving effect,and the wind resistance of the ship reduced 11.1% and the corresponding fuel consumption reduced about 0.4% when the wind speed is 7 m/s that is often encountered in the object ship.