International Shipbuilding Progress - Volume 3, issue 21

Authors: Horn, F.

Article Type: Research Article

DOI: 10.3233/ISP-1956-32101

Citation: International Shipbuilding Progress, vol. 3, no. 21, pp. 243-254, 1956

Authors: Gerritsma, J.

Article Type: Research Article

Abstract: The exciting forces and moments are calculated for a normal cargo-passengership with zero velocity in longitudinal waves. These calculations are based on the Froude-Kriloff hypothesis and on the velocity potential for waves of small amplitude according to Lamb. The influence of second order quantities (such as the Smith effect or the inclusion of relative velocity) on the exciting forces and moments is considered, as well as the influence of the coupling between heaving and pitching motions. The same calculations are made for a mathematical model, and a comparison is made with published experimental results.

DOI: 10.3233/ISP-1956-32102

Citation: International Shipbuilding Progress, vol. 3, no. 21, pp. 255-264, 1956

Authors: Storey, A.

Article Type: Research Article

Abstract: The principal developments in connection with the Doxford marine Diesel engine in the past few years have been the development of supercharging and the extensive use of boiler fuel. An outline is given of the development work undertaken in the supercharging of the Doxford engine and a brief survey of the experiences at sea. The characteristics of the supercharged two cycle opposed piston engine are described together with a resume of technical and commercial advantages of supercharging. Similarly, a description is given of the employment of boiler fuels and of the advantages to be gained. A description is …given of difficulties encountered and methods developed for overcoming these. The diaphragm engine and oil cooling of the lower pistons have been developed for the Doxford engine particularly to enable boiler fuel to be used and to eliminate the troubles. A new fuel injection system has been developed, known as the Timing Valve Injection System, and a description is given of the characteristics of this system together with a survey of the advantages. In conjunction with this new fuel system a new air starting system has been developed, which together enable reversing and manoeuvring to be accomplished with a single lever. Prospects of improving the termal efficiency and rating of marine two cycle engines are reviewed together with proposed methods of achieving mechanical simplification. Show more

DOI: 10.3233/ISP-1956-32103

Citation: International Shipbuilding Progress, vol. 3, no. 21, pp. 265-284, 1956

Authors: Verhagen, C.J.D.M. | de Does, J.C.

Article Type: Research Article

Abstract: In this article a brief description is given of a special stress analyser, built for the Shipbuilding Department of the Technological University at Delft, Holland. The strains are measured by means of strain-gauges, forming a complete Wheatstone bridge. The output of this bridge is supplied to the analyser and in this instrument the amplitude and level of the stress-cycles are registered by means of a number of counters. The strainrange is divided into 9 levels, and as will be easily seen, this leads to 45 counters. With the help of these counters every possible combination of amplitude and level within …the range of the instrument may be registered. The first design of the instrument was made by ir. P.J. Rademakers at the Instrumentation Department of the University, the further development and the building of the apparatus was done by ir. C.M. Verhagen and mr. A. van Westbroek of the Technical Physics Department T.H.-T.N.O. Show more

DOI: 10.3233/ISP-1956-32104

Citation: International Shipbuilding Progress, vol. 3, no. 21, pp. 285-289, 1956