International Shipbuilding Progress - Volume 8, issue 77

Authors: Jaeger, H.E. | Nibbering, J.J.W.

Article Type: Research Article

Abstract: This report describes the work carried out in the Ship Structure Laboratory of the Technological University, Delft, Netherlands, by the authors, in order to clarify the behaviour of beam knees and other bracketed connections under dynamic and static loads. The report first gives a general view of the function of a beam knee or bracket in the structure of a ship. It explains the theory underlying the behaviour and influence of bracketed connections as applied to ship’s structural problems and the necessity of investigating dynamic load influence by tests. The results of static and dynamic tests are analysed …and a general view is given on the construction of adequate bracketed joints. Some tests give information about effective beam knee-connections, without the use of bracket- or gusset plates, by butt welding orthogonally connecting adjacent members. An approximate calculation method is given for predicting bracket stresses. Parts of this report were published by the authors in the bulletin of the “Association Technique Maritime et Aéronautique”, Paris, in 1959 and 1960 [17] and [18]. Show more

DOI: 10.3233/ISP-1961-87701

Citation: International Shipbuilding Progress, vol. 8, no. 77, pp. 3-42, 1961

Authors: Greger, O.

Article Type: Research Article

Abstract: After a historical summary on the development of propeller guiding apparatus reference is made to the effect of the Costa propulsion bulb. A series of tank tests with this device and with relative test arrangements are described; results are given which were obtained with self propelled models. Then, the results obtained on full size ships are discussed and the importance of evaluating service results by means of modern statistical methods and of effecting comparative trials according to standardization rules is emphasized. As often as possible additional vibration measurements and steering trials should be made. The improvements obtained with Costa propulsion …bulb on models and full size ships are then compared and the existing differences explained. Recent flow experiments gave a further means of studying fundamental phenomena, e.g. the influence of the Costa propulsion bulb can directly be observed. In conclusion it is stated that model tests with Costa propulsion bulb are both a valuable help to recognize the influence of certain features in bulb design and a proof of the effectiveness of the bulb on modern ships. Show more

DOI: 10.3233/ISP-1961-87702

Citation: International Shipbuilding Progress, vol. 8, no. 77, pp. 43-53, 1961