Question

According to the energy equation, which of these properties remain constant along the flow?

(a) Total enthalpy

(b) Total entropy

(c) Kinetic energy

(d) Potential energy

The question was posed to me by my college professor while I was bunking the class.

My question comes from Governing Equations in portion Quasi-One-Dimensional Flow of Aerodynamics

Answer 1

Correct option is (a) Total enthalpy

To explain: The energy equation stated for steady quasi – one – dimensional flow is given by h1 + \(\frac {u_1^2}{2}\) = h2 + \(\frac {u_2^2}{2}\). According to this formula which is derived for the adiabatic flow, the total enthalpy remains constant (h0 = 0).