The solution of this is, of course, a family of curves, with a para- 

 meter (g/d), with K plotted against d/L. However, for the purpose of this 

 table, only one value of g/d will be used because usually the instrument 

 is placed on the bottom (g/d = 1). In this case 



K = 



cosh 27Td/L~ (16) 



Values of K are shown in column 7 of the tables. 



Fraction of Energy Advancing With the Velocity of the Wave Crest ; 

 According to the irrotational wave theory only a fraction of the total 

 wave energy travels forward with the wave form (that is, with the wave 

 velocity C rather than the group velocity C_)* The equation for this 

 fraction, n, is 



n - I |~1 + 4 7T d/L "1 



Sinh And/L (17) 



Values of this term are shown in column 11 of the tables . 



Ratio of Group Velocity to Deep-Water Wave Velocity ; 



C G /C = G G /C . C/C Q - n tanh 2 tt d/L (18) 



See column 12 of the tables for this term. 



Energy Coefficient ; This term is defined by the expression** 

 M » TT" 2 



2 tanh 2 2frd 



in the equation for the energy of waves 

 E = WL H 2 n _ M 



(19) 



g— (1 - * -Hi-) (20) 



IT 



■2 

 See column 14- of the tables for values of M. 



* A Summary of the Theory of Oscillatory Waves, Technical Report 

 No. 2, Beach Erosion Board, Washington, D. C, 1942. p 32 . 



** Wave Action in Relation to Engineering Structures, by D. D 

 Gaillard, The Engineer School, Fort Belvoir, Virginia. 

 Reprinted 1935« 



