Sec. 62.3 ESTIMATE OF ADDED LIQUID MASS 423 



TABLE 62.a — Body Characteristics and Added Liquid-Mass Coefficients fob a Series of 31 Forms 



R'l is the 0-diml radius of curvature at the tail. 

 It is R^L/D^, where Ki is the absolute radius of 

 curvature at the tail. 



C/. is the prismatic coefficient, = ¥/[k{Q.5D)'L] 



ki is the added-mass coefficient Cam for un- 

 steady longitudinal or surging motion, parallel to 

 the a;-axis 



/c2 is the added-mass coefficient Cam for un- 

 steady lateral or sidling motion, parallel to the 

 2/-axis. 



fca is the added mass moment of inertia co- 

 efficient Cam for rotation in pitch, nose up and 

 nose down, about the horizontal transverse axis 

 at midlength. 



The shape of the fore-and-aft meridian section 

 is defined by a sixth-degree polynomial. 



Table 62. a gives the numerical results of the 



work of Landweber and Winzer, for a series of 

 31 bodies of revolution of varied characteristics. 



62.3 Comparison of a Vibrating Ship with a 

 Vibrating Geometric Shape. The deeply sub- 

 merged submarme is approximated reasonably 

 well by the general (elliptic) eUipsoids described 

 in Sec. 62.2 or by the family of bodies of revolu- 

 tion with fore-and-aft asymmetry listed in Table 

 62.a. 



The surface ship floating in equilibrium, with 

 its hull partly immersed and partly exposed, when 

 subjected to unsteady motion in any one of its 

 six degrees of freedom, is surrounded by a flow 

 pattern which is by no means well known, except 

 possibly for the case of straight-ahead motion. 

 Figs. 20.G, 20.H, and 20.1 of Volume I indicate, 

 in frankly schematic fashion, the probable 



