Stagnation enthalpy

When the potential energy of the fluid is negligible, the mass-specific stagnation enthalpy represents the total energy of a flowing fluid stream per unit mass.

Often it is expressed in specific quantities, where specific means mass-specific, to get an intensive quantity: where: The volume-specific version of this equation (in units of energy per volume, [J/m^3] is obtained by multiplying the equation with the fluid density

: where: The non-specific version of this equation, that means extensive quantities are used, is: where: The suffix ‘0’ usually denotes the stagnation condition and is used as such here.

The stagnation enthalpy adds a term associated with the kinetic energy of the fluid mass.

[2] The total enthalpy for a real or ideal gas does not change across a shock.