Question

What is the region of influence?

(a) Area outside right running wave

(b) Area within the upstream characteristics

(c) Area within the downstream characteristics

(d) Area outside the left running wave

This question was posed to me in homework.

This question is from Region of Influence and Domain of Dependencies topic in chapter Numerical Techniques for Steady Supersonic Flow of Aerodynamics

Answer 1

Right choice is (c) Area within the downstream characteristics

The best I can explain: For a point A which is present in a flow field with incoming steady supersonic flow, there will be two characteristic lines passing through them. The area formed between these two characteristics in the downstream region is known as region of influence.