International Shipbuilding Progress - Volume 5, issue 42

Authors: Zoller, R.E.

Article Type: Research Article

Abstract: An extended surface consisting of studs resistance-welded to 1 ( 1 / ( / 2 in. tubes was hurriedly conceived for naval economizers during the war. Minor modifications have met the needs of nuclear heat exchangers and modern merchant and fighting ships. Its use in many well-known fleets is first enumerated followed by a discussion of the different requirements of nuclear-power plant. Sixteen different designs of extended surface were tested in clean conditions, some being repeated on wider spacings, staggered and in-line. Each test series is analysed by means of simplified heat-transfer and …draught-loss formulae enabling interpolation to design various tube banks. The various surfaces are compared by calculating the characteristic dimensions of heat exchangers with identical performance. Finally the laboratory tests are compared with the trial results of economizers on highly rated boilers. Show more

DOI: 10.3233/ISP-1958-54201

Citation: International Shipbuilding Progress, vol. 5, no. 42, pp. 51-66, 1958

Authors: Vedeler, Georg

Article Type: Research Article

DOI: 10.3233/ISP-1958-54202

Citation: International Shipbuilding Progress, vol. 5, no. 42, pp. 67-77, 1958

Authors: Jefferson, J.L. | Turner, R.C.

Article Type: Research Article

Abstract: The paper, with a reference to the economics of blade manufacture, explains the reasons for the main series of tests, which were carried out at the National Gas Turbine Establishment, the material being supplied by C.A. Parsons and Company, Limited. Four series of tests are described in detail. Various combinations of shrouding and tip clearance were investigated, untwisted constant-section blading being used in the first three series. The experiments were carried out over a range of shrouding leakage clearances, and also included an investigation of the boundary layer flow on the convex surface of a stator blade in the compressor. …A brief review of published work on the effects of normal radial tip clearance is followed by a description of some early results obtained on a multi-stage compressor. It is concluded that shrouding of the type investigated should, if possible, be avoided, especially under certain aerodynamic conditions. If it is necessary that it be used, the clearance should be maintained at the smallest practicable value. The use of very fine radial tip clearances may also result in a loss of performance, although values in excess of 1 per cent. of the blade height are also shown to be undesirable in the particular case investigated. Show more

DOI: 10.3233/ISP-1958-54203

Citation: International Shipbuilding Progress, vol. 5, no. 42, pp. 78-101, 1958