Convergence problem!
 

Hello

I am simulating a transient problem using Fluent and have convergence problem.

Although I increase the number of iterations per time step, the solution does not converge.

I have attached two screenshots: first: iteration history, 2- lift coefficient

I have tried to decrease the time step, increase the iterations per time step but it seems they cannot affect the convergence.

Have you ever had a problem like this?

Hi :D

there are many approaches to enhance a chance of the convergence

if you could give an information about your problem, that will be nice

(Ps. sorry about wierd sentences , I'm not good at english)

I'm simulating the flapping and pitching movement of a 3D wing simultaneously. The motion of the wing has been defined using a UDF code.

Specifically, I need to plot lift and drag coefficients curves.

As the solution does not converge, at some point the residuals start increasing and then the curve becomes wavy.

I'm using smoothing and remeshing dynamic mesh methods.