16 



2 3 



Speed In knots 



Figure 18 - Computed Full-Scale Drags of Buoys 1, 2, and 3 Compared 

 with Experimental Full-Scale Drag of Buoy 1 



flowing normal to the axis of the cylinder tends to oscillate with frequency 

 n given by Strouhals number 



^ - 0.185 



where d is the diameter of the cylinder in feet and 

 Vis the velocity in feet per second (3) 



TARE DRAG RESULTS 



The tare drag of the strut, which was deducted from the total drag 

 of the buoys and the strut combined, is the mean of the tare drag data ob- 

 tained from tests on the strut when it was towed in the wake of the buoys. 

 Figures "1 4 to 18 are curves in which the mean tare drag for the respective 

 buoys is plotted against speed. 



Figure 19 presents test data of the buoys in the form of a plot of 

 drag coefficient versus Reynolds number. The drag coefficient is defined as 



