If Airy theory had been used K^)^ = 0.17, and 



- - r?^ > n ( ^H = 0.76H, (0.38) 



Some of the difference between the two values of C^ is because the 

 SWL (instead of the wave crest) was the upper limit of the integration 

 performed to obtain K^ for Airy theory. The remaining difference 

 is because Airy theory is unable to describe accurately the water- 

 particle velocities of finite-amplitude waves. 

 ************************************* 



The two examples show the influence of the wave theory used on the 

 value of Cjj determined from a field experiment. Since the determina- 

 tion of wave forces is the inverse problem, i.e., Cp and wave conditions 

 known, it is irrportant in fovae calculations to use a wave theory that is 

 equivalent to the wave theory used to obtain the value of C^ (and C^) ^ 

 A wave theory that accurately describes the fluid motion should be used 

 in the analysis of experimental data to obtain Cj^ (and C/i^) and in 

 design calculations. 



Results obtained by several investigators for the variation of C^ 

 with Reynolds number are indicated in Figure 7-58. The solid line is 

 generally conservative, and is recommended for design along with Figures 

 7-44 and 7-46 with the Reynolds number defined by Equation 7-38. 



************** 



EXAMPLE PROBLEM *************** 



DETERMINE : Were the values of Cp used in the preceding example problems 

 reasonable? 



SOLUTION : For the first example with H = 10 ft., T = 10 sec, d = 15 ft. 

 and D = 1 ft., from Equation 7-40, 



ttH 



L 



T L^ 



Trio 1 



IT 0^ ^ '■'' f^-/^^" 



From Equation 7-39, 



R„ = 



V 



(7.66) (1) 

 1 X 10-5 



= 7.66 X 10^. 



7-107 



