Main Page | See live article | Alphabetical index In fluid dynamics, Bernoulli's Equation describes the behavior of moving fluids along a streamline. v = fluid velocity along the streamline g = gravitational constant y = elevation in g-field P = pressure along the streamline ρ = fluid density These assumptions must be met for the equation to apply: Inviscid flow - Viscosity (internal friction) = 0 Steady flow Incompressible flow - ρ is constant The equation applies along a streamline. The equation can be derived by integrating the Euler equations along a streamline. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.