Dynamic interaction of the cavitating propeller tip vortex with the rudder

• Autorzy: Szantyr J. A.
• Języki publikacji: EN

Abstrakty

EN

The hydrodynamic interaction between the ship propeller and the rudder has many aspects. One of the most interesting is the interaction between the cavitating tip vortex shed from the propeller blades and the rudder. This interaction leads to strongly dynamic behaviour of the cavitating vortex, which in turn generates unusually high pressure pulses in its vicinity. Possibly accurate prediction of these pulses is one of the most important problems in the hydrodynamic design of a new ship. The paper presents a relatively simple computational model of the propeller cavitating tip vortex behaviour close to the rudder leading edge. The model is based on the traditional Rankine vortex and on the potential solution of the dynamics of the cylindrical sections of the cavitating kernel passing through the strongly variable pressure field in the vicinity of the rudder leading edge. The model reproduces numerically the experimentally observed process of initial compression of the vortex kernel in the high pressure region near the stagnation point at the rudder leading edge and subsequent explosive growth of the kernel in the low pressure region further downstream. Numerical simulation of this process enables computation of the additional pressure pulses generated due to this phenomenon and transmitted onto the hull surface. This new numerical model of the cavitating tip vortex is incorporated in the modified unsteady lifting surface program for prediction of propeller cavitation, which has been successfully used in the process of propeller design for several years and which recently has been extended to include the effects of propeller – rudder interaction. The results of calculations are compared with the experimental measurements and they demonstrate reasonable agreement between theory and physical reality.

Słowa kluczowe

EN

propeller blades; rudder; cavitating; tip vortex shed

• Wydawca: Gdańsk University of Technology, Faculty of Ocean Engineering & Ship Technology
• Czasopismo: Polish Maritime Research
• Rocznik: 2007
• Tom: nr 4
• Strony: 10--14
• Opis fizyczny: Bibliogr. 10 poz., rys., tab.

Twórcy

autor

Szantyr J. A.

• Gdansk University of Technology

Bibliografia

• 1. Couty Ch., Farhat M., Avellon F.:Physical Investigation of a Cavitation Vortex Collapse. Proceedings of the 4th Intern. Symp. on Cavitation CAV2001, Pasadena, USA, 2001
• 2. Krasilnikov V.I., Berg A., Oye I.J.: Numerical Prediction of Sheet Cavitation on Rudder and Podded Propeller Using Potential and Viscous Flow Solutions. Proceedings of the 5th Intern. Symp. on Cavitation CAV2003, Osaka, Japan, 2003
• 3. Kuiper G.: New Developments Around Sheet and Tip Vortex Cavitation on Ship Propellers. Proceedings of the 4th Intern. Symp. on Cavitation CAV2001, Pasadena, USA, 2001
• 4. Lee H.S., Kinnas S.A. et al.: Numerical Modelling of Propeller and Rudder Sheet Cavitation Including Propeller – Rudder Interaction and the Effects of the Tunnel. Proceedings of the 5th Intern. Symp. on Cavitation CAV2001, Pasadena, USA 2001
• 5. Lee S.K.: Numerical Study – Propeller/Rudder Cavitation of Fast Containership. Proceedings of the 3rd Intern. Shipbuilding Conference, St. Petersburg, Russia, 2002
• 6. Shen Y.T, Remmers K.D. Jiang C.W.: Effects of Ship Hull and Propeller on Rudder Cavitation. Journal of Ship Research, Vol.41, No. 3, 1997
• 7. Szantyr J.A.: Analytical Prediction of Propeller Cavitation. The Naval Architect July/August 1991
• 8. Szantyr J.A.: A Method for Analysis of Cavitating Marine Propellers in Non-uniform Flow. Intern. Shipbuilding Progress Vol.41, No.427, 1994
• 9. Szantyr J.A.: A Computational Model of the Propeller Cavitating Tip Vortex Interacting With the Rudder. 6th International Conference on Cavitation CAV’06, Wageningen, The Netherlands, 24-26 September 2006
• 10. Tunc M., Delale C.F.: Energy dissipation due to fission of cavitating bubbles. Proceedings of the 5th Intern. Symp. On Cavitation CAV2003, Osaka, Japan, 2003