Optimization Design And Aerodynamic Characteristics Analysis Of Typical Wing-tail Combination

The wing-in-ground effect(WIG)ship is a new type of high-performance ship that flies at a low altitude on the sea surface.The research on the wing-in-ground effect ship has received increasing attention.The main structure of the ground-effect wing ship includes the ground-effect wing,the ground-effect wing end plates,the main hull and the stern.The main function of the ground-effect wing is to provide lift to the main hull.Therefore,previous studies have been conducted mainly on ground-effect wings.Different from the ground-effect wing,the tail of the ground-effect wing ship is in the non-ground-effect area.Its main function is to adjust the pitch attitude of the WIG to achieve the purpose of regulating the overall stability of the WIG.The current research on the tailplane is in the primary stage and has a high research space.For the purpose of practical application,it is necessary to fully consider the influence of wave shape change on the aerodynamic characteristics and motion stability of the typical ground effect wing-tail-fuselage combination,which is very necessary for the overall design of the ground effect wing ship.In the past,the research on WIG mainly used numerical simulation and model tests.This thesis first summarizes and analyzes the research methods of WIG at home and abroad.The previous research methods have the following drawbacks.Most of the research on numerical simulation failed to fully consider the influence of other components of WIG on the aerodynamic characteristics of WIG.Generally,due to the limitation of computing resources,the incoming flow velocity is usually used instead of the flight speed.Most of the previous research is carried out at a certain speed.Previous experimental research mainly adopts the method of wind tunnel test,which often fails to consider the influence of wave factors on its aerodynamic characteristics.In this thesis,the aerodynamic characteristics of the wing-tailfuselage combination under wave action are studied by numerical simulation and model towing test.The specific research contents include:(1)In this thesis,the research status of the WIG ship at home and abroad and the aerodynamic characteristics of the WIG-tail-fuselage combination are analyzed and summarized.In order to fully consider the influence of wave factors on the aerodynamic characteristics of WIG,the computational fluid dynamics(CFD)method is used to capture the free surface by using overlapping grid technology and the volume of fluid(VOF)method.By verifying the convergence of the grid,the size of the grid is determined.Then,the aerodynamic characteristics of typical wing-tail-fuselage combination under wave action are simulated and compared with the model towing test results to verify the the method’s accuracy.(2)For the typical NACA ground effect wing-tail-fuselage combination,the STARCCM+ software is used to simulate the typical NACA ground effect wing-tail-fuselage combination during take-off.The plane carrier motion method is used to simulate the uniform acceleration process.The angle of attack of the ground effect wing and the relative spacing of the ground effect wing-tail are optimized and analyzed.It is concluded that the ground effect wing-tailfuselage combination has better aerodynamic characteristics when the angle of attack is 6 °and the relative spacing is 0.36 m.The “S” type ground effect wing with better stability is selected.From the research results,compared with the aerodynamic characteristics of the typical NACA ground effect wing-tail-fuselage combination,the “S” ground effect wing-tailfuselage combination has better aerodynamic characteristics.(3)In this thesis,the CFD method is used to select the angle of attack of the ground effect wing and the relative distance between the ground effect wing and the tail wing with good aerodynamic characteristics,and the numerical simulation of the “S” type ground effect wingtail-fuselage combination is carried out.Firstly,the influence of wave height and period parameters on its aerodynamic characteristics is studied.At the same time,according to the principle of determining the motion stability of the wing-tail-fuselage combination,the motion stability of the “S” type wing-tail-fuselage combination is studied.The results show that the “S” type wing-tail-fuselage combination has high flight stability.(4)In order to ensure that the research is more accurate,the model towing test method is used to carry out the towing tank towing test on the typical ground effect wing-tail-fuselage combination and the “S” type ground effect wing-tail-fuselage combination respectively.The aerodynamic characteristics under the action of still water and waves are studied.In summary,this thesis uses the CFD method to optimize the angle of attack and relative spacing of the ground-effect wing-tail assembly。 The ground-effect wing-tail assembly with better aerodynamic characteristics is optimized and selected.At the same time,the "S" type ground-effect wing-tail assembly with better aerodynamic characteristics was selected and the aerodynamic characteristics of the "S" type ground-effect wing-tail wing-fuselage assembly were also studied.In order to ensure more accurate results,a model drag test was conducted on a typical wing-tail-fuselage assembly and an "S" type wing-tail-fuselage assembly.The aerodynamics of the ground-effect vessel was studied more accurately by the test method.