Question

For an irrotational flow, the velocity component along z-direction becomes _________

(a) 0

(b) 1

(c) infinity

(d) -1

This question was posed to me by my school teacher while I was bunking the class.

I want to ask this question from Source Flow in chapter Inviscid & Incompressible Flow of Aerodynamics

Answer 1

Correct choice is (a) 0

To explain I would say: In irrotational flow, the fluid flows in linear direction only and if the stream function exits the flow may be either rotational or irrotational. When the stream function satisfies the Laplace equation, it the case of irrotational flow.