321 



The data for the dimensionless wave length of significant vaves in the 

 channel fit Wiegel's correlation curve satisfactorily. There is a tendency, 

 however, for our points to lie somewhat above the estimate of Wiegel's line. 



A plot of the wind tunnel data for fj^ indicates that Wiegel's curve is 

 again approached. However, in this case, our data lie somewhat below the 

 estimated correlation curve. This is somewhat misleading, however, since 

 comparatively little data is presented for this value (in terms of P) in 

 Wiegel's paper. 



The dimensionless energy spectrum derived by Eq. (12) can be compared 

 to the dimensionless form discussed by Bretschneider (1963a and 1963b), 

 provided that it is assumed that a^/f^j is approximately equal to 

 C^k $^ where ♦„, is the maximum value of the spectral density 

 function (see, for examples, the values in Table III). This has been done 

 and the comparison is shown in Figure 19. Bretschneider 's estimate for 

 the Neumann spectrum corresponding to fully developed sea is shown along 

 with our dimensionless spectrum. For further comparison, typical data of 

 Burling as calculated by Bi*etschneider are shown in Figure 19 . As might be 

 expected, the dimensionless spectrum for waves at very short fetch in the 

 channel is narrower than Burling 's data taken at F = 1000 meters and the 

 Neumann spectrum for nearly infinite fetch. The three dimensional character 

 of waves developing on the surface of the oceans 'or lakes, of course, cannot 

 be reproduced in the channel. 



Acknowle dgement 



The wind- water tunnel at Colorado State University was constructed under 

 a matching grant from the National Science Foundation. This work was supported 

 by the National Science Foundation in connection with its grant to Colorado 

 State University, and its contract with the National Center for Atmospheric 

 Research. The authors are grateful to R. Biro, C Goodwin, Eosein Shokouh, 

 C. Yang and many others for their efforts in carrying out the experimental 

 program and analyzing the extensive data of this study. 



