International Shipbuilding Progress - Volume 4, issue 37

Authors: Hims, H.E.C.

Article Type: Research Article

Abstract: Trials of this nature, which may last up to three years and in the fully comprehensive sense have been confined so far to warship machinery, are described in detail. Menton is made of trials of merchant-ship machinery rather more restricted in scope. The value of the comprehensive trials is emphasized, together with the planning of the programmes, operation, and some points of instrumentation. Some fundamental principles for the conduct of such trials are stated, based on experience, and the Author seeks to expand the circle in which these arc appreciated as sound axioms.

DOI: 10.3233/ISP-1957-43701

Citation: International Shipbuilding Progress, vol. 4, no. 37, pp. 455-466, 1957

Authors: Tachmindji, A.J. | Milam, A.B.

Article Type: Research Article

Abstract: The present report gives the results of calculations for the optimum circulation distribution for propellers having a finite number of blades and finite hub diameters. The calculations were performed for hub diameters of 0.2, 0.3 and 0.4 of the propeller diameters and a method for interpolating between these values is also included.

DOI: 10.3233/ISP-1957-43702

Citation: International Shipbuilding Progress, vol. 4, no. 37, pp. 467-477, 1957

Authors: Radosavljević, Lj.B.

Article Type: Research Article

Abstract: The motion of a ship in a seaway was considered by A.N. Kriloff in his two well known papers [1] and [2] in 1896–98. In [1] A.N. Kriloff concluded that the difference between the hydrostatic distribution of buoyancy and the distribution following Gerstner’s theory of waves, the so-called Smith Effect, has no important influence on the motion of a ship, so that it can be neglected. This opinion has prevailed up the present. So, for instance, on the basis of that conclusion, G.P. Weinblum and M. St. Denis, have neglected the Smith Effect, when discussing in the paper [3] the …motions of a ship in a seaway. In the present paper the author considers the motion of a ship in a seaway on the same assumption as A.N. Kriloff, except that he: a. takes into consideration approximately the influence of added mass; b. accepts the cosinusoidal wave profile, and c. substitutes the real hull surface by approximative analytical expressions corresponding to the coefficients and the main dimensions of a ship. For the case were the length of the waves λ is equal to the length of the ship L , the author shows that Smith Effect can not be neglected, and that the decreases of amplitudes caused by it can be over 50% for heaving, and over 30% for pitching. The author gives the diagrams by means of which it is possible to estimate approximatively Smith Effect, and to determine the heaving and the pitching of a ship in every particular case, when the waterplane coefficient α , the block coefficient δ and the main dimensions of a ship: the breadth B , the length L and the draft T are given. Show more

DOI: 10.3233/ISP-1957-43703

Citation: International Shipbuilding Progress, vol. 4, no. 37, pp. 478-490, 1957

Authors: Cruz, José

Article Type: Research Article

DOI: 10.3233/ISP-1957-43704

Citation: International Shipbuilding Progress, vol. 4, no. 37, pp. 491-494, 1957

Authors: van Manen, J.D.

Article Type: Research Article

DOI: 10.3233/ISP-1957-43705

Citation: International Shipbuilding Progress, vol. 4, no. 37, pp. 495-502, 1957