Study On The Open Water Performance Of The Whale Tail Wheel Propeiler

Whale Tail Wheel(WTW)propeller is a newly developed ship propeller.Compared to the traditional propeller,WTW has the advantages of high efficiency and environmentally friendly nature when the ship navigates with low and moderate forward speeds,which has potential application value in the field of energy saving and emission reduction.At present,the research on the WTW is still at the primary stage in the world wide,and the analysis of its propulsion performance is not comprehensive.In this thesis,both theoretical method and computational fluid dynamics method(CFD)are used to study the open water performance and the preliminary design method of WTW.The research contents and the results of this thesis are as follows:(1)By analyzing the working principle of the WTW,a theoretical model based on steady-state assumption is established to calculate the WTW performance.For a self-designed WTW,use MATLAB to calculate its hydrodynamic performance under different working conditions.And the optimum swing angle of the blade is obtained when the propulsive efficiency reaches the highest.(2)Based on the analysis of the WTW oscillation law and its flow field characteristics,a CFD model is developed to study the open water characteristics of the WTW.The model is used to calculate the performance of a cycloid propeller.By comparing the numerical simulation results with the experimental results,it is proved that the CFD model can be used to calculate the open water performance of WTW.(3)By using the CFD model,the hydrodynamic performance of the WTW under different working conditions is calculated.The results show that the WTW can maintain high propulsive efficiency in a wide speed range.By comparing the CFD results with the theoretical results,the feasibility and deficiency of the theoretical method are obtained.(4)Using CFD methods to analyze the influence of different blade number,blade chord length,blade length and end plate size on WTW open water performance.On this basis,the mechanism of flow interaction between blades is discussed,and a method of modifying the blade swing curve to improve the performance of WTW is proposed.Finally,for WTW with a diameter of 1m,the overall propulsion performance is better when the blade number set as 5,blade chord set as 0.25 m and blade length set as 1.2m.(5)Proposed a design plan of a WTW for a propeller propulsion ship.The hydrodynamic performance,geometric size and power of the WTW are compared with that of the propeller.Through the design case,it is considered that for the ship with low speed,using WTW can achieve higher efficiency than traditional propellers.Due to WTW can improve energy saving ability of the ship,it has the potential to be applied on the ship.