EngineerHub.orgWhat this calculator does
Applies the steady incompressible energy equation between two points. Solve for pressure, velocity, elevation, or required pump head while accounting for head loss and turbine extraction.
Inputs
Results
Pressures must use the same reference: both absolute or both gauge. The equation assumes steady, incompressible, one-dimensional flow along a streamline.
What the equation represents
Bernoulli’s equation is a mechanical-energy balance per unit weight of fluid. Pressure head, velocity head and elevation head can exchange with one another as fluid moves through a system.
Why it is useful
It links conditions at two locations and can solve for an unknown pressure, velocity, elevation or ideal pump head. It is widely used for nozzles, tanks, siphons, pipe systems and preliminary pump studies.
How to define the two points
Choose two stations along the same flow path. Enter pressure P, mean velocity V and elevation z at each station using one common elevation datum and one common pressure reference—both gauge or both absolute.
Pumps, turbines and losses
Pump head adds mechanical energy. Turbine head removes useful mechanical energy. Head loss represents irreversible dissipation from pipe friction, fittings, valves, entrances and exits.
Assumptions and limits
The implemented form assumes steady, incompressible, one-dimensional flow with kinetic-energy correction factor equal to one. Large density changes, unsteady transients, multiphase flow and major heat effects need a more complete control-volume energy model.