On the Turning of Towed Ships System

We have discussed the steady turning motion of the towed ships system in this Journal No. 137. In this paper, we discussed again the turning of the towed ships system by the parameters as used in No. 137 and the additional parameter κ (radius of gyration of ship), the results are as follows : 1. By steered the rudder of the tugboat, the effects of the fore-towing point, towing ropes' length and the towed ships to the values ofAd0, Tr0, Tad0 and Re0 are small and it can be neglected, and those values are given in equation (7).2. The larger the rudder angle and the rudder area ratio of the tugboat are the smaller the values of Ad, Tr and Tad are.3. As the rudder angle and rudder area of the tugboat are constant, a). the values of Ad, Tr and Tad decrease, when the number of towed ship increases, b). because of the increase of the radius of steady turning, the values of Ad, Tr, Tad become larger, when the the towing points are placed apart from the centre of gravity of the towed ship, except the last towed ship, c). the effects of the derivatives of towed ships are included in the parameter it as given in equation (4), d). the effect of radius of gyration of tugboat itself is large, when the value of radius of gyration of tugboat increase, the values of Ad, Tr and Tad grow large, and the effect of radius of gyration of towed ship is small and negligible.