Study On Three Energy Saving Devices Based On CFD Technology

Nowadays,climate change,environmental pollution and resources shortages are more and more serious,especially the crisis of serious supply of resources has already become a main factor for restricting human being development.Based on the severe situation,international community has given an enthusiastic response and put forward countermeasures.Energy-saving emission was promote worldwide vigorously.Maritime transport is an important channel for international trade import and export,it has the benefit of high volume and low cost.However,when the ship sailing on the sea,it has a dramatic consumption of fuel oil and large amounts of greenhouse gases were pumped out into the atmosphere.This has aroused widespread attention over the world.In addition,affected by the financial crisis,shipping market suffers a severe downturn,but the fuel cost keeps high,this brings serious financial trouble to many shipping enterprises.Shipowners are keen to refit their ships to reduce operating costs.Based on the general concern of the international community and shipping enterprises urgent requirements,the design and development of energy saving devices now becomes a hot topic which attracts lots of research institutes and shipyards at home and aboard.In the past,the energy saving devices was studied through experimental method.But experiment always consumes lots of effort,time and money.CFD technique has been developed mature gradually in the recent years,it has the benefits of high accuracy in calculation,low consumption of resources and convenient operation and so on.Then the research and development of energy saving devices obtains new impulsion.Energy saving device for ship can be divided into three catalogues: energy saving device in front of propeller,energy saving device after screw propeller and special propulsion.This paper chooses three typical energy saving devices and respectively analyzes their hydrodynamic performance by using CFD technique.Some specific jobs are as follows:Firstly,this paper carries out the simulation of the open water performance of MAU5-50 propeller and VP1304 propeller by using commercial CFD software STAR-CCM+ for the validation and verification of numerical calculation method.Secondly,the open water performance of Grim Vane Wheel and propeller is studied by numerical simulation and the energy saving effect under different number of GVW blades,different diameters of GVW and different axial installation position is analyzed.Thirdly,this paper analyzes the energy-saving effect of propeller-GVW-rudder system.Fourthly,this paper compares the energy conservation effect of two typical Pre-swirl stator: Asymmetrical PSS and Symmetrical PSS.Then the principle of energy saving of PSS is studied.At last,it perform the simulation of its hydrodynamic performance of Tandem Ducted Propeller and Tandem Propeller.And the control variable method is adopted to study the influences of angular spacing,pitches between propellers,diameters of Duct and attack angles of Duct on the open water performance.