Question

Oil (specific gravity of 0.80 and a viscosity of 0.000042 lbf/ft2) at a temperature of 80 F flows through two separate pipes 10 and 12 inches in diameter. if the mean velocity of flow in the 12 in. pipe is 6 ft/s, the velocity of flow in the 10 in pipe will be:

Answer 1

The velocity of flow in 10in pipe is 4.16 ft/s.

Step-by-step explanation:

Given that

Specific gravity = 0.8

Viscosity =0.00042
`lbf/ft^2`

For pipe 1

`V_1=6 ft/s,d_1=12\ in`

For pipe 1

`V_2,d_1=10\ in`

If we assume that flow in the both pipe is laminar

For laminar flow through circular pipe

`(\Delta P)/(L)=(32V\mu )/(d^2)`

So same pressure drop we can say that

`(V_1 )/(d^2_1)=(V_2)/(d^2_2)`

`(6)/(12^2)=(V_2)/(10^2)`

`V_2=4.16 ft/s`

So the velocity of flow in 10in pipe is 4.16 ft/s.