Question

Water is flowing in a pipe with a varying cross-section area, and at all points the water completely fills the pipe. At point 1 the cross-section area of the pipe is 0.080 m^2, and the magnitude of the fluid velocity is 2.50m/s. Calculate the volume of the water discharged from the open end of the pipe in 1 second.

Answer 1

For incompressible fluids in steady state flow, the volume rate of flow is constant along the flow direction. What goes in must come out at the same rate, in volume per second. This is called the "continuity equation".

Therefore
A* V = 0.08 * 2.50 = 0.20 m^3/s
is the volume flow rate at the discharge end, and everywhere else.