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Lubrication Shell Physic 2D

Francesc-Xavier Borras

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Hi all,

I am working with the Lubrication Shell Physic (this is aleady defined):

h = h0 (initial geometry) + hw(deformation on the solid wall) + hb (deformation on the channel base)

The only problem is h0.

I am trying to simulate a tilting-pad thrust bearing. The idea is:

"A hinged bar on a pivot point(intermediate position) and it should be placed in the position that the sum of moments in the bar is null."
This "bar" is the "h" from the Shell Lubricant.

I have already found the mathematical solution so I want to include:

A FUNCTION:

ht = k*x + n

AND A GLOBAL EQUATION:

State Variable: k
Expression: intop1(pf*(La-x))=0 [=sum of moments equals 0 on the tilting pad]

In order to achieve:

h = h0 (intial geometry) + ht (tilting correction) + hw (deformation on the solid wall) + hb (deformation on the channel base)

(ht can be added in the h0 gap)

How will you do that? I tried everything and I am not able to do it... thanks in advance.

3 Replies Last Post Feb 20, 2012, 10:49 a.m. EST
Francesc-Xavier Borras

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Posted: 1 decade ago Feb 13, 2012, 1:24 a.m. EST
Hej! I am still having the problem... I need to post the file for a better understanding? May be my explanation is not good enough.
Hej! I am still having the problem... I need to post the file for a better understanding? May be my explanation is not good enough.

Francesc-Xavier Borras

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Posted: 1 decade ago Feb 20, 2012, 10:10 a.m. EST
Hi again,

I did some improvements (I hope).

Now I have a problem with 4.2a than can easily be solved with 3.5 extruding the deformation to the other surface.

Anyway I am using the 4.2a.

Lubricant Shell Physics.

I modelled two rectangles with different materials, one represents the solid wall and the other the channel base. I make both suffer a deformation (Solid mechanics) from the pressure,

I want to take into account the displacement of the solid wall and of the channel base into the "Lubricant Shell" (into the Reynolds Equation)

For the solid wall is easy, you only need to couple the deformation from the Solid Mechanics.

For the channel base, the software does not allow me to couple it with the Solid Mechanics as I did with the solid wall. I do not have the possiblity.Why? How to solve it?
Hi again, I did some improvements (I hope). Now I have a problem with 4.2a than can easily be solved with 3.5 extruding the deformation to the other surface. Anyway I am using the 4.2a. Lubricant Shell Physics. I modelled two rectangles with different materials, one represents the solid wall and the other the channel base. I make both suffer a deformation (Solid mechanics) from the pressure, I want to take into account the displacement of the solid wall and of the channel base into the "Lubricant Shell" (into the Reynolds Equation) For the solid wall is easy, you only need to couple the deformation from the Solid Mechanics. For the channel base, the software does not allow me to couple it with the Solid Mechanics as I did with the solid wall. I do not have the possiblity.Why? How to solve it?

Francesc-Xavier Borras

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Posted: 1 decade ago Feb 20, 2012, 10:49 a.m. EST
The main question is:

How does the software know the "channel base" deformation if I did not input it?

The edge you select is the "solid wall" and if that edge is from a "solid mechanic" domain then you can couple it with the "lubrication shell".

However, the software does not ask you for any adge to define the "Channel Base", how does it know the propieties of the "Channel Base"? How to define the "Channel Base"?

Thanks again.
The main question is: How does the software know the "channel base" deformation if I did not input it? The edge you select is the "solid wall" and if that edge is from a "solid mechanic" domain then you can couple it with the "lubrication shell". However, the software does not ask you for any adge to define the "Channel Base", how does it know the propieties of the "Channel Base"? How to define the "Channel Base"? Thanks again.

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