Abstract
This paper presents a method to predict ship wake from measured model wake by applying the theory of two-dimensional turbulent wake. From basic investigations on two-dimensional wing, the following physical properties of turbulent wake were made clear with respect to the scale effect on viscous wake.
(1) The width of wake is in proportion to the momentum thickness and not to the scale of model and ship.
(2) Velocity distribution in wake varies downstream as a function of non-dimensional distance divided by momentum thickness.
(3) The value of the wake peak is affected significantly by the difference of the velocity profile at the stern frame between model and ship.
In the well-known Sasajima-Tanaka's method only the first item of above is taken into account for scaling the viscous wake.
The method for predicting ship wake was developed in view of the above properties. Applicability of the method to the wake of ship was examined by use of the geosim models of a cargo ship and it was shown that the method presented here provides reasonable results and can be applied as a practical means for predicting ship wake.
