Types of Fluid Energy

Types of Fluid Energy

1.0 POTENTIAL ENERGY

2.0 KINETIC ENERGY

3.0 WORK or FLOW ENERGY

Then:

= Flow Energy

Total Energy @1 = Total Energy @2

Divide by the weight of the water (w):

Units?

OR:

Elevation Head (m) + Velocity Head (m) + Pressure Head (m) = Total Head

In a “real” situation:

Where:

HP = head produced by a pump (m)

HT = head taken out of the system by a turbine (m)

HL = head losses due to friction with side walls, valve parts, couplers, etc. This value is often available from pipe and component manufacturers.

Friction loss can be calculated from:

Where:

f = the fiction factor of the pipe,

L = the length of the pipe,

D = the diameter of the pipe, and

v = the velocity of the fluid in the pipe

So:

· as gets smaller (long pipe of small diameter), then HL gets larger OR

· as the velocity increases (higher flow rate or same flow through a smaller pipe), then HL gets larger

Example:

Specify a pump capable of supplying 40 USgpm (2.5 L/s) at 40 psi (276 kPa) to a facility located 125 ft (38.1 meters) above the water level in a well through a 2 inch (50mm) diameter polyethylene pipe that is 3280 ft (1000 meters) long.

Pump Selection Web Site

http://www.pump-flo.com/select/centrifugal/manual.aspx