Appendix D 

 CALCULATION OF SEAWATER INTAKE 



The method used to calculate the total quantity of seawater intake by the spheres depends on 

 obtaining the change in number of chain links suspended off the seafloor by a sphere. The reduction in 

 number of links is converted into quantity of seawater intake, Q. The accuracy of determining Q is 

 dependent on several approximations. 



One approximation is the criterion by which the submersible operators counted the chain links. They 

 counted only whole links; or, in other words, the bottom-most link counted was the one in a vertical 

 position. 



Another approximation is estimating the original number of links suspended off the seafloor when the 

 spheres had dry-concrete walls. The associated calculations are shown below, in part, and are completed in 

 Table D-1. 



Buoyancy of Hull 



Dimensions D^ = 65.886 inches and D; = 57.640 inches 

 Weight of Displaced Seawater, Wq 



Wj, = 64 pcf (86.64 cu ft) = 5,545 lb 

 Weight of Concrete Sphere, W^^ 



Wc = 145.2 pcf (28.625 cu ft) = 4,156 1b 

 Positive Buoyancy = 1,389 lb for bare concrete hull 

 In-Water Weight of Components on Spheres 



5/8-inch chain 67 lb 



Wet-concrete control block 220 lb 



Steel components 40 lb 



Titanium components 8 lb 



Load on Spheres 7-16 (also common load to other spheres) . . . . 335 1b 



Clock (estimated in air weight) 20 lb 



Batteries (estimated in air weight) 40 lb 



Common load +3 3 5 lb 



Load on Spheres 1-6 395 1b 



Steel bar reinforcement (in-water weight) 150 1b 



Common load +335 lb 



Load on Spheres 17 and 18 485 1b 



Column D in Table D-1 was another approximation. This was the apparent weight gain of the system 

 due to the change in volume of the sphere under load. Using data from Reference 8, it was assumed that the 

 maximum long-term strain for the spheres at greatest depths was 2,500 jdinjin. This strain resulted in a 



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