236 



HYDRODYNAMICS IN SHIP DESIGN 



Sec. 51.9 



(\) V. S. Mnritimc Commission Cl-M-.\Vt rlnss of iho 

 1940'». The plan of the aflerl)0»ly ami of the wafer- 

 linen nnd run of thin vesBcl lire illuxtrnttHl in Figs, 

 ."il.n and 51. K, resp«'elivcly. These lines are included 

 as an e.xnmple of a stern that is definitely too blunt, 

 with slope.i that are exoe.isivo for goo<l flow to the 

 propeller. This chiss was te.'itod as TMB model 

 3S39, and the complete model results are given in 

 SNA.ME RD sheet 19. 



(5) U. S. Maritime Commission CS ty|)c cargo vessel, for 



which a IkkIv plan is to be found in SXAME, 1950, 

 Fig. 77 on p. 5t)3. This class was tested as TMB 

 model 35:J4, but at the time of writing (1955) the 

 complete results had not yet been embodied in an 

 S.\.\MK RD sheet. 



(6) To<ld, F. H., and Forest, F. X., ".\ Proposed New 



Basis for the Design of Singli>^orew Merchant >Ship 

 Forms and Standard Scries Lines," SNAME, 1951, 

 pp. (}42-744. This paper covers the TMB Series 57 

 forms. 



(7) Todd, F. H., "Some Further Experiments on Single- 



Screw Merchant Ship Forms— Series 60," SN.\ME, 

 1953, pp. 516-5S9. This pajx^r gives all the data in 

 sufficient detail to indicate the exact forms of the 

 various models, their hull coefficients, and their 

 distribution of section area along the length. It also 

 gives corresponding data for the U. S. Maritime 

 Commission C-2 class of cargo ship, for the ^lariner 

 class, for the modified C-3 vessel Schuyler Olis 

 Bland, for a Bethlehem design of cargo vessel, and 

 for the tanker Pennsylvania. 



(8) Rus-oo, V. L., and Sullivan, E. K., give a body plan 



of the Mariner cla.ss, including a wave profile at a 

 speed of 20 kt and a T, of 0.S77 (SNAME, 1953, 

 p. 1 15 and Fig. 12 on p. 122|. This design was tested 

 as TMB model 4358\V-3. The stern profiles, both 

 closed (as tested in model scale) and open, as built 

 into the shijis, are shown in Figs. 13 and 14, pages 

 123 and 125, respectively, of the reference. 



(9) A small-scale body plan of the Gopher Mariner is 



published by V. L. Russo and R. T. McGoldrick in 

 SNAME, 1955, Fig. 9 on p. 449 



(10) II. De Luce and W. I. H. Budd give a body plan, 



wave profile, and some lines of flow around the 

 tanker Pennsylvania [SNAME, 1950, Fig. 7, p. 430] 



(11) Body plans, and in many cases lines drawings, are 



published by J. Baader for a great variety of large 

 and small single-screw vessels in his book "Cruceros 

 y Lanchas Veloces (Cruisers and Fast Launches)," 

 published in Buenos Aires in 1951, Figs. 225-239, 

 pp. 287-301. 



Typical body plans for .sliallow-wiilcr paddle- 

 driven vessels are (^ivoii in Figs. 72. A, 72. B, and 

 72.D. 



Limitations of space i)recliide the roprodiu'tion 

 of lines drawinns, body plans, or even tabulated 

 data on other interesting and instructive designs. 

 Indeed, in view of the availability (in 19oG) of 

 some 100 SXAME Resistance Data sheots, with 

 their wealth of quantitative data, and with the 

 prospect of additional sheets year by year, the 



marine architect has ready at hand a very con- 

 siderable amount of reference data. 



The Index sheets and Summarj' sheets accom- 

 panying RD sheets 1 through 150 (and later) add 

 to the store of information and present it in a 

 slightly difTerent fa.shion. 



51.9 Twin-Screw Body Plans. The general 

 comments of Sec. 51.8 relative to single-screw 

 ships, including the notes on the SXAME RD 

 sheets, Index sheets, and Summarj' sheets, apply 

 to twin-screw vessels as well. Among the ships 

 (or designs) for which body plans arc available 

 in the literature there may be mentioned: 



(1) .\tlantic liner ^fanhaitan, represented by TMB mo<lel 



3041. Fig. 17 on p. HI of SNAME, 1947. General 

 characteristics of the hull are given in Table 3 on 

 p. 113 of the reference. 



(2) Twin-skeg Manhattan design, tested in small scale 



as TMB model 3898 but never worked up as a 

 ship design or built as a ship. Body plans are shown 

 in Figs. IS and 24 on pp. 112 and 116, respectively, 

 of SNAME, 1947. General characteristics of this 

 design are given in Table 3 on p. 113 of the reference. 



(3) Proposed design of a large tanker of extremely wide 



beam, developed by the Sun Shipbuilding and Dry 

 Dock Company, tested in small scale as T.MB 

 models 3817 and 3821. The lines are shown in Fig. 

 11 on p. 107 and Fig. 13 on p. 108 of SNAME, 1947. 

 Table 1 on p. 109 gives the general characteristics 

 of the proposed ship. 



(4) TMB model 3930, representing a twin-sorew liner, 



745 ft long on the waterline, with a normal form of 

 -stern (Bates, J. L., SNAME, 1947, Fig. 41, p. 137). 

 The body plan is accompanied by a table of general 

 characteristics. 



(5) Bates, J. L., "Large Piissenger-Carrying Ships for 



Certain Essential Trade Routes," SNAME, 1945, 

 pp. 290-334. Table 1 on page 296 lists the principal 

 dimensions and characteristics of the five designs 

 described in the paper. 



(6) TMB model 3917, representing a tunn-screw liner, 



745 ft long on the waterline, with a twin-skeg stern 

 (Bates, J. L., SNAME, 1947, Fig. 42, p. 137). 

 The body plan is accompanied by a table of general 

 characteristics. 



51.10 Multiple-Screw Sterns. A great ?iiMn- 

 ber of quadruple-screw ve.s.sels iiave been liuilt in 

 the period 1000-1955, yet the published data on 

 lines, form coefficients, hull parameters, and other 

 hydrodynamic features are surprisingly meager. 

 In fact, data on the shape of the runs, the jiropeller 

 positions and diameters, hull (tip) clearances, and 

 shape of appendages carrying the jiropeller .'jhafts 

 are limited largely to stern jihotdgraphs of these 

 ves.sels on the laimching ways or in dock. 



In the late l<,l20"s and early HMO's, T. E. Ferris 

 made many studies of a large, high-speed trans- 



