Bernoulli's Principle

A fluid dynamics principle stating that for steady, incompressible, nonviscous flow along a streamline, an increase in flow speed corresponds to a decrease in pressure (or potential energy per unit volume), conserving total mechanical energy along the streamline.

For steady, inviscid, incompressible flow along a streamline (neglecting shaft work and heat transfer), the sum of static pressure p, dynamic pressure ½ρV² and hydrostatic term ρ g z is constant: p + ½ρV² + ρ g z = constant; this relation expresses conservation of mechanical energy per unit volume along the streamline under its assumptions.