Stagnation point enthalpy

Since pipe flow is more nearly isenthalpic, the flash fraction x is found from an enthalpy balance between the stagnation point and a point z downstream. Accounting for changes in potential energy, kinetic energy, and heat added or removed from the pipe Q, x is given by ... 

At the stagnation point (where ue = 0) the recovery enthalpy is identical to the stagnation enthalpy even for Prr 1. Thus, from the definition of Nu and Re, the local heat flux at the stagnation point in airflow for the speed range up to 30,000 ft/s (9144 m/s) can be expressed as... 

As was pointed out by Spalding [15], some aspects of the analysis of combustion waves in which kinetic energy is of importance can be simplified by using the stagnation enthalpy (CpT + v /2) as a variable. A normalized dimensionless measure of the stagnation enthalpy is... 

---