Question

The quantity at a point in a subsonic flow where the element is speeded up to sonic velocity adiabatically is defined as_____

(a) Static local temperature, T

(b) Stagnation local temperature, T°

(c) T*

(d) Standard temperature

I got this question in an internship interview.

My question comes from Definition of Total Stagnation Conditions in portion Compressible Flow – Preliminary Aspects of Aerodynamics

Answer 1

Correct option is (c) T*

The best I can explain: The T* is defined as the temperature at a point where the local static temperature is T, in the sonic flow when the fluid element is speeded up to sonic velocity adiabatically. Also, T* is the temperature when the supersonic fluid element is slowed down to sonic velocity adiabatically.