Question

Determine the pressure difference in N/m2,between two points 800m apart in horizontal pipe-line,150 mm diameter, discharging water at the rate of 12.5litres per second. Take the frictional coefficient ,f, as being 0.008​

Answer 1

Answer:
`10.631* 10^3\ N/m^2`

Step-by-step explanation:

Given

Discharge is
`Q=12.5\ L`

Diameter of pipe
`d=150\ mm`

Distance between two ends of pipe
`L=800\ m`

friction factor
`f=0.008`

Average velocity is given by

`\Rightarrow v_(avg)=(12.5* 10^(-3))/((\pi )/(4)(0.15)^2)\\\\\Rightarrow v_(avg)=(15.9134* 10^(-3))/(2.25* 10^(-2))\\\\\Rightarrow v_(avg)=7.07* 10^(-1)\\\Rightarrow v_(avg)=0.707\ m/s`

Pressure difference is given by

`\Rightarrow \Delta P=f\ (L)/(d)(\rho v_(avg)^2)/(2)\\\\\Rightarrow \Delta P=0.008* (800)/(0.15)* (997* (0.707)^2)/(2)\\\\\Rightarrow \Delta P=10,631.45\ N/m^2\\\Rightarrow \Delta P=10.631\ kPa`