IlVnRODVX AMK.S IN SHIP DKSIGN 



Sec. 52.3 



bulbs, /, = 0.08, O.OJ, ami 0.(X), witli the vortical 

 scales exftggeratetl about 7 times, are given by 

 E. M. Bragg in SNAME, 1930, PI. 51: 



r, - v/Vl 



1.2 



1.0 



0.8 



Station for first bow-wsvo crest abaft FP, 

 on a basis of 20 stations 



About 1.7, approx. 0.0S5/y from FP. Varied 

 from Sta. 1.6 to Sta. 1.9 for the three 

 modoLs referenced 



About 1.2, approx. 0.06A from FP. Varied 

 from Sfa. 1.0 to Stas. 1.6 or 1.7 for the 

 three models 



About 0.8, approx. O.OIL from FP. Varied 

 from Sta. 0.7 to Sta. 1.0 for the three 

 models. 



The author of this paper comments on the fact, 

 still unexplained, that despite the amazing 

 similarity of the \va\'e profiles for all three models 

 at a T, of 1.2, the model with the largest bulb had 

 15 per cent less resistance than the one with no 

 bulb. The present author makes the further 

 comment that, at all three T, values, the model 

 with the largest bulb had the highest bow-wave 

 crest! This feature likewise remains unexplained. 



0. Schlichting, in his 1934 STG paper on tests 

 of models in shallow and restricted waters, 

 referenced in Sec. 61.3, gives in Figs. 13a and 13b 

 the wave profiles alongside models of a heavy 

 cruiser and a light cruiser, respectively, for values 



of /•'. varying from 0.21 to 0.38, T, of from 0.71 

 to 1.28. 



The wave profile for a double-ended model 

 having mathematical lines is given on Plat« 1, 

 page 545 of a paper on wake by C. Igonet [ATM A, 

 1938, Vol. 42, pp. 543-5G9]. This plate shows not 

 only a body plan of the model but a transverse 

 profile of the water surface abreast the model at 

 Stas. 1 and 19, corresponding to 0.05 and 0.95L 

 from the FP. 



E. Ileckscher published a scries of wave pro- 

 files alongside a given model, for F„ values of 

 0.19, 0.23, 0.25, 0.295, and 0.325, T, of 0.(54, 

 0.775, 0.842, 0.991, and 1.091, corresponding to 

 five hump-and-hollow positions along the curve 

 of resistance with speed [WRH, 15 Aug 1939, 

 Fig. 4, p. 2G2]. 



In the Annual Report of the Rome Model Basin 

 for the year 1941, Vol. X, there are showTi two 

 wave profiles for Rome model C.295, at two 

 speeds. The corresponding T, values are 1.082 and 

 1.204. These profiles, with the body plan of the 

 model, as published in Table XII of the refer- 

 enced report, are reproduced here in Fig. 52. E. 



D. W. Taylor shows the wave profiles for two 

 models at various speed-length quotients [S and 

 P, 1943, Figs. 21-25, p. 24]. Wave profiles are also 

 traced on the body plans of two series of models 

 \vith \videly varying midsection coeflRcients in 

 Figs. 26-35 on page 25 of the reference. This set 

 of body plans is reproduced as Fig. 52. Q in Sec. 

 52.7 of the present chapter. 



G. do Verdi6rc and J. Gauticr give a series of 



Wave Rrofile for Tq- I 204, F„-0359 Water Surtace at Re^t 



V ^ — 



Fia. S2.E Obbeiivko Wavk 1'iiorii.Eu on Uomk Munr.L Bakin Moiiei, C.:^05 



