A water tank is at atmospheric pressure. Initially, the tank water level is at 20 ft from the drain centerline. We now open the drain and assume there are no frictional losses. If A e / A t = 0.015,...

A water tank is at atmospheric pressure. Initially, the tank water level is at 20 ft from the drain centerline. We now open the drain and assume there are no frictional losses. If
A_e
/A_t

= 0.015, find the time to drain the tank.

Consider two rectangular tanks having constant flow areas of
A
₁
and
A
₂. The tanks are connected at the bottom by a frictionless pipe of diameter
d. The first tank is filled with water up to an elevation h₀
from the connecting pipe. We now open the isolation valve. a) Show that the time for levels to equalize is given by:

b) Find the time in second if h_o
= 3 m,
d
= 5 cm,
A
₁
= 3 m²,
A
²
= 2 m², and
C_d

= 0.61.