Question

a pipe having inlet and outlet diameter 20 cm and 10cm respectively. The velocity of water which is following through the pipe at inlet section is 4 m/s. find the velocity head at inlet and outlet sections and also find discharge.​

Answer 1

Answer:

0.8155m, 13.0479m, 0.1256 m^3/s

Explanation:

Di= 20cm

Do= 10 cm

Vi= 4m/s

Applying Continuity Equation for flow in one direction assuming incompressible steady flow.

AiVi = AoVo

π/4 * Di^2 * Vi = π/4 * Do^2 * Vo

(20^2) * 4 = (10^2) * Vo

=> Vo = 16m/s

Now,

Velocity Head is given by (V^2)/2g

So,

Velocity head at inlet = (4*4)/(2*9.81) =0.8155m

and,

Velocity head at outlet = (16*16)/(2*9.81) = 13.0479m

Also,

Discharge, Q = AiVi = AoVo

Q = (π/4) * (0.2*0.2) * 4

Q = 0.1256 m^3/s