[Bajji]

Hi all,

I have to simulate the orbit(path taken by the centre ) of the shaft in a foil bearing with air as the lubricant instead of oil. The foil bearing is same as the Journal bearing except that the boundary is deformable and not rigid like a journal bearing. There is a pressure build up because shaft is rotating and dragging the air around it into a narrow channel.(See image) I obviously need to solve the

a) Pressure build up in the fluid
b) Deformation of the boundary due to the built up pressure.
c) Motion of the shaft centre inside the bearing in response to the pressure and its own rotation.

Hope I am clear.

1) Has anyone solved this in OpenFOAM before.?
2) what are the solvers I should read up on?

Any pointers to start or links to similar solved problems will be very usefull.

[elvis]

Hi,
maybe http://powerlab.fsb.hr/ped/kturbo/Op...dicPhD2005.pdf
Doctorate Thesis: Advanced Modelling of Elastohydrodynamic Lubrication by
Petra Brajdic-Mitidieri
http://powerlab.fsb.hr/ped/kturbo/Op...riImperial.pdf

is something for you

[Bajji]

Thanks Elvis.

I will see what Brajdic has done in his Thesis.

[fpierart]

Originally Posted by Bajji

Thanks Elvis.

I will see what Brajdic has done in his Thesis.

Bajji, could you finally model the bearing?, I need to do the same and if you can help me, with something like with solver did you use (rhoSimplecFoam, rhoCentral foam) or more datails I will be very helpull.

[Bajji]

Hi fpierart,

I did finally model the bearing with shaft motion inside it.

But I gave up on openFOAM and wrote the Reynold's equation solver (I tried FDM and FVM) in C++ from scratch. It worked. I got pretty good agreements between simulated and published pressure distributions at mid plane.

I want to make clear that it was not a problem with openFOAM. I simply couldn't get that monster working.

Have great time,
Balaji Sankar.