problem with Iteration during solving the reynold equation

Hi everybody,

im trying to calculate two variables (pressure and film thickness of air in an air-bearing) by solving a Reynold-equation using iteraion-loop. The problem is that whenever i change the iteration condition (e by Pn+1 - Pn < e ) i get a different answer which is by very little values of e not correct (and too high). That means that the result increases in inverse propotion to e. I have tried also using relaxation-factor but not a very big change happened.

any answer will be appreciated. tnx

Answer 1

[Carpenter86]

Since the relaxation did not help and you get convergence but the solution is incorrect, the problem may be in the discretization of equations. Maybe you should start with a simplified solution first by fixing the geometry and then solving only for pressure. You can use a sphere on flat as an example, in this case the pressure distribution have a nicely defined shape. You can also find a matlab code for analytical solution and numerical solution for the lubricated cases, but I think this may help you.