Guide Card, Part 5

Fluid Kinetic Energy

The kinetic energy of a moving fluid is more useful in applications like the Bernoulli equation when it is expressed as kinetic energy per unit volume 

When the kinetic energy is that of fluid under conditions of laminar flow through a tube, one must take into account the velocity profile to evaluate the kinetic energy. Across the cross-section of flow, the kinetic energy must be calculated using the average of the velocity squared , which is not the same as squaring the average velocity. Expressed in terms of the maximum velocity v_m at the center of the flow, the kinetic energy is

 

Fluid Potential Energy

The potential energy of a moving fluid is more useful in applications like the Bernoulli equation when is expressed as potential energy per unit volume 

The energy density of a fluid can be expressed in terms of this potential energy density along with kinetic energy density and fluid pressure.