A Study Of The Fluid Dynamic Performance Of Jet Rudder

Jet rudder is a new type of rudder with high efficiency that acquires comparatively higher lift by injecting a small volume of liquid, so it greatly improves the efficiency of the rudder, and has a foreground of R&D in marine vessel application. However, thorough research for jet rudder has just started, the research is still in the phase of scheme design at home and abroad, and the primary mode of research is basically experimental research. The research of jet rudder's fluid dynamical performance through theoretical method has a significance of guidance for the improvement of design level of jet rudder.With the background of pure potential flow theory, the method of line distributing is used to study the hydrodynamics of jet rudder.While the rudder angel is small,the results with jet effects could agree the case well.With the panel method on the basis of shoot flow theoretics,the paper labour the seperation of trail eddy and make some change to the wing cotaning the distance frome trailand volute,according to circle streameof cylinder and separation. Frome the calculational results,we can see that this method could be the correct to the former method. Through the effects of changing line distributing on the surface of jet rudder and the changed position and shape of the votex after aerfoil seperation, making the model of the jet rudder and the hydrodynamic perfomace of experiment rudder is studied. The jet rudder also can make lift performance .without rudder angle and ratio of lift or resistance has an obvious increasing in every angle .to the different rudder fountain and converge influence is different .the coefficient increase with the rudder. The calculation will be emanative when jet velocity has a great discrepancy from the ship velocity.The curve of lift and resistance is nearly the same as experiment. So the method of simulating the jet rudder using fountain and converge could be used to calcilate the dynamiacs of rudder.Single flap rudder or jet rudder both has an obvious effec of increasing lift.This can improve the manoeuvre polity of ship.Therefore rises a new flap-jet rudder and makes a calculation to forecast its dynamic performance.This new rudder could offer more lift and little resistance.After the calculation of jet rudder with several C_μs and different rudderangels, the results are compared and analyzed with model experimental data of jet rudder, and some beneficial conclusions are reached, then the method of calculation of jet rudder fluid dynamic performance through panel method is proposed, and the conclusion reached provides some foundation for further research of this kind of new model rudder.