The wave-making resistance of ships: a theoretical and practical analysis

Abstract

The theoretical investigation of the total resistance to the forward motion of a ship is usually simplified by regarding it as the sum of certain independent terms such as the frictional, wave-makings and eddy-making resistances. The experimental study of frictional resistance leads to a formula of the type. R s =ƒSV m , (1) where S is the wetted surface, V the speed,ƒ a frictional coefficient, and m an index whose value is about 1.83. After deducting from the total resistance the frictional part calculated from a suitable formula of this kind, the remainder is called the residuary resistance. Of this the wave-making resistance is the most important part; the present paper is limited to the study of wave-making resistance, and chiefly its variation with the speed of the ship. The hydrodynamical theory as it stands at present may be stated briefly.