BERNOULLI'S EQUATION: for Ideal Fluid Flow


Bernoulli's Equation is basically a statement of the conservation of energy per unit volume along the pipe.

Energy Density or Energy per unit Volume (SI: J/m3):

For an ideal fluid flow the energy density is the same at all locations along the pipe. This is the same as saying that the energy of a unit mass of the fluid does not change as it flow through the pipe system.

* A compressed fluid or gas has the ability to do work if it is allowed to expand, i.e. it has stored energy. The magnitude of the pressure P is equal to the Potential Energy per unit volume due to the Hydrostatic Pressure in the fluid. Note that the unit of pressure even can be expressed at a unit of energy density, Pa = N/m2=(N. m)/(m2 . m) = J/m3.
* The kinetic energy density can be though of a pressure exerted by the fluid due to its motion.
* We have already seen that gravitational potential energy density, ρgh, is just the pressure of a fluid due to its weight.