Flow Development: Is psi = 4y - (y^3)/3 Fully Developed?

[banerjeerupak]

Homework Statement

The following stream function holds for a certain flow of water at 20 C.
psi = 4y - (y^3)/3.

Is this flow fully developed?

Homework Equations

psi = 4y - (y^3)/3.

The Attempt at a Solution

How am i suppose to tell if a flow is fully developed or not from the stream function? Direct me to what should i study to find the answer.

 

[banerjeerupak]

I found the solution ..so here it is... for a flow to be fully developed, it should have no change in the u component. i.e. du/dx = 0