ANSYS simulation gives significant deformation but minimal stress!

[redherring1001]

I am currently trying to flesh out the deformation and stress patterns in the cartilages and soft tissues of a human body joint; I've been able to see a decent deformation pattern but no matter how much I refine the mesh by reducing element size/changing relevance center, I can't make it give me a good stress pattern. With a coarse mesh I got random spots of higher stress, and when I make it finer those spots simply disappear. The colour codes for stress go from the lowest (blue) up to 117 MPa (red), but I don't see anything red in the tissue that is supposed to have maximum equivalent stress, according to the results. On the other hand, I see a good circular deformation pattern in the key soft tissues (highest deformation at the centre). Shouldn't the stress pattern correspond to this, i.e. with highest stress at the centre? Can anyone who's faced this problem/knows how to deal with it please help?

 

[Dave442]

Is it possible that the stresses observed in one region of your model (the cartilage, for example) are much higher than those observed in the soft tissues? If so, when you generate a contour plot, the stresses within the soft tissues will all fall within the lower bands of the scale and appear blue? If this is the case, you just need to adjust the limits of your contour plot? If you post an image and describe the material models you have used and the applied loading it would be easier to comment.

 

[IRstuff]

Please refrain from double posting.

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