## Covered Surface

Barrier Ball® is composed of spheres that are autoconfigured in such a way that the covered liquid surface is always 91% regardless of the diameter of the sphere. This is calculated as follows:

**Equilateral triangle Area ABC (A1)**

A1 = (√3·r²)/4**Area A-e-d (S1)**

S1 = ½ · R ² · Ѳ (where r is the radius of the sphere and Ѳ = π/3)

S1 = ½·r²· π/3

S1 = π·r²/6**Outdoor Area (S2)**

S2 = A1 – 3·S1

S2 = r²·(√3-π/2)**% Uncovered Area (Ad)**

Ad = (S2/A1)·100

Ad = 9

## Therefore, BarrierBall® coverage is 91% (100% – Ad)

## Wind Resistance

Wind is one of the main factors influencing evaporation, the inner weight of the barrier Ball spheres makes them resistant to the wind in such a way that the system maintains its effectiveness in the presence of it.

**P = (Cd * Ro * V2) / 2**

P = Wind pressure (N/m2)

Ro = dry air density = 1,223 Kg/m3 (1ATM and 15 º C)

V = Wind velocity (m/s)

Cd = aerodynamic coefficient of resistance to advance = 1.17 (flat surface)

= 0.50 (Sphere)/0.25 (half-sunken sphere)

= 0.05 (aerodynamic surface)

## BarrierBall® wind resistance = 200 km/hr