Table 7. Comparison of angles giving pile 

 channel geometry, 6, half-width 

 of front maximum region, x> and 

 minimum location, (f), for Figure 31, 





e 



X 



* 



1x2 H-pile 



76.3° 



56° 



124° 



1x1 H-pile 



65° 



59° 



121° 



2x2 H-pile 



65° 



38° 



115° 



2x1 H-pile 



48.2° 



46° 



80° 



5x1 H-pile 



18.2° 



33° 



81° 



The patterns in Figure 31 also show that with, deeper channels, the 

 pattern minimums occur at lower yaw angles, and the rear secondary max- 

 imum is higher. Table 7 includes the angular location of the center of 

 the minimum for these patterns. Although the values of <^ are less 

 objective than the values of x, the correlation coefficient for the 

 five (e,(f)) pairs is 0.866, so the hypothesis that there is no linear 

 relationship between and cj) can be rejected with 93.7-percent con- 

 fidence. The relationships between _e, x, and cj) can be more firmly 

 established by considering all the [Vii&)/\^] data sets in Appendix C with 

 clearly defined angles x and <(). For the 5 piles listed in Table 7, 

 there are 25 suitable data sets, giving 50 values of both x and i> ' 

 Fitting straight lines yields 



X = 36.0° + 0.30 8 , 

 with a correlation coefficient of 0.520, and 



4- = 65.7° + 0.63 e . 



(4) 



C5) 



with a correlation coefficient of 0.777. Each of these correlation 

 coefficients is large enough to provide 100-percent confidence that there 

 IS a linear relationship between and x, and between 6 and d.. 

 Thus, pile channel geometry definitely affects the shape of the peak 

 water pattern for high waves. This conclusion is consistent with the 

 data m Figures 32, 33, and 34. 



Figures 32 and 33 present peak water patterns for piles of similar 

 shape but different sizes; Figure 32 shows data for low and high waves 

 at T = 1.55 seconds incident on the 1x1 and 3x3 H-piles; and Figure 33 

 shows data for a high wave at T = 3.10 seconds incident on the 1x1 and 

 2x2 H-piles. The larger pile generally causes a slightly higher front 

 maximum, a more sharply defined front maximum region, and a lower rear 

 maximum; peak forward flow is less obstructed by the smaller pile. How- 

 ever, each pattern of a pair is basically similar to the other 



56 



