Study On Rapidity Performance Of Next-generation River-sea Going Ship

Transportation between Changjiang River and seaports by River-Sea goingmanner becomes more popular nowadays, it’s also a obvious tendency that the sizeof cargo ships is growing persistently. Several limits changed such like thatChangjiang channel development in the recent future according to "12th Five Year"Plan and that CCS approves direction calculation as structure perfomance checkingmethod will benefit the size of river-sea ships growing up further. So there arerequirements of new-generation river-sea going ships from inland waterage industryin order to reduce operationcost and enhance their competitiveness, meanwhile alsorequirements of rapidity and structure performance improvement according toenergy-saving policies from authorities. Special Ship Project "Next-genetationriver-sea ship development" sponsored by MIIT China has been undertaken in recentyears, which has combined improvement on hydrodynamic performance, structureperformance and etc. Investigations in this paper are parts of the rapidityperformance study of the project.A thesis review of Computational Fluid Dynamics and its application on shiprapidity study is performed, followed by describing of numerical approach tosimulate flow around hull with propeller and to predict self-propulsion performance,then the benchmark including KCS ship and KP505propeller adopted widely arechosen to validate the CFD approch. At last of the paper shipform and energy-savingdevices of the project are developed and improved by CFD and EFD approach.In order to simulate flow around a surface ship with propeller(s), a body forcemodel is built in this paper based on thrust and torque distribution of a real propellerand also on wake distribution, which alleviates the conflict between accuracy andtime cost. The method is used in simulating flow around KCS and river-sea ship,and shows its accuracy in predicting rapidity performance and flow detailscomparing with experiment result. Other approaches such as open water calculationof a propeller and free surface flow around hull are also validated by experimentalresults. Self-propulsion tests of the twin-skeg river-sea ship are performed with inwardand outward rotating propellers respectively, so pre-swirl efficiency is deduced fromthe total propulsion efficiency, which leads more accurate prediction of the effectivewake than that from a popular single-revolution self-propulsion test method. So thedual-revolution test method adopted in the paper can supply more accurateparameters to the propeller design of a real hull.River-sea going ship of the project is typical a low-speed full hull with higherblock coefficient, higher beam to depth ratio and lower length to beam ratio thanthat are operational, which brings more difficulties to improve rapidity performance.CFD and EFD method are adopted combinatorially to retrofit fore-and aft-bodyrespectively to improve rapidity performance of the river-sea ship. Further more,shallow water effects on ship resistance and navigation gesture are studied in thisthesis and an tentative simulation of flow around a full-scale hull is also conducted.Energy saving performance of a new kind of ESD(Energy Saving Device) wasstudied at the end of the thesis, which is composed by a simi-compensating ductcombined with pre-swirl stator at downside. Model test result analysis shows thatthis ESD performs well in uniforming and pre-swirling inflow of the propeller,which saves energy consumed.