Rudder-ship interaction in steady state and oscillatory rudder tests on a ship model

Article type: Research Article

Authors: Burcher, R.K.^a | McKendrick, G.^b | Price, W.G.^c | Stonehouse, M.^{d; *}

Affiliations: [a] AMTE (Haslar) | [b] American Bureau of Shipping, London | [c] Ministry of Defence, RCNC, Bath | [d] Department Mechanical Engineering, University College London

Note: [*] Presently Department Mechanical Engineering, Brunel University, Uxbridge, Middlesex.

Abstract: A series of model tests are described in which steady state and oscillatory rudder derivatives are measured. During the experiments undertaken in a circulating water channel, the model ‘travelling’ at prescribed forward speeds was either restricted or allowed freedom to roll. The difference in the forms of the side force measurement records obtained from the oscillatory rudder tests are discussed with emphasis on the interaction between rudder and roll motions. In the steady state rudder tests the changes in the measured side forces caused by the forced roll were very small but in the dynamic tests, depending on forward speed, amplitude and frequency of rudder oscillation, large roll motions could be generated resulting in significant changes in the measured side forces. Additional tests with the model fixed relative to a wave are described. With the rudder positioned at four points along the wave, its effectiveness and interaction with the hull are further discussed.

DOI: 10.3233/ISP-1982-2933802

Journal: International Shipbuilding Progress, vol. 29, no. 338, pp. 260-269, 1982