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Volumetric locking
Posted Jun 10, 2014, 6:39 a.m. EDT Structural Mechanics 2 Replies
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Hi all,
I have a question regrading the volumetric locking in using FEM with COMSOL
I plan to use linear elasticity in COMSOL for the nearly in-compressible material (ex. poisson's ratio, nu=0.49). We all know that this will result in the volumetric locking of the element without any special treatment.
As I know, ANSYS uses "Extra shape function technique" and "Reduced integration technique" in SOLID45 and SOLID185 solvers respectively to overcome the locking.
I would like to know how COMSOL treats the volumetric locking for the incompressible materials
Best wishes,
I have a question regrading the volumetric locking in using FEM with COMSOL
I plan to use linear elasticity in COMSOL for the nearly in-compressible material (ex. poisson's ratio, nu=0.49). We all know that this will result in the volumetric locking of the element without any special treatment.
As I know, ANSYS uses "Extra shape function technique" and "Reduced integration technique" in SOLID45 and SOLID185 solvers respectively to overcome the locking.
I would like to know how COMSOL treats the volumetric locking for the incompressible materials
Best wishes,
2 Replies Last Post Jun 10, 2014, 9:36 a.m. EDT
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Posted:
1 decade ago
Hi,
You select the 'Nearly incompressible material' checkbox to enable the mixed ('hybrid'; 'u-p') formulation.
Regards,
Henrik
You select the 'Nearly incompressible material' checkbox to enable the mixed ('hybrid'; 'u-p') formulation.
Regards,
Henrik
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Posted:
1 decade ago
Hi Jichul,
To be precise ANSYS element SOLID45 overcomes volumetric locking via Reduced Integration not the Enhanced Strains … those are for shear locking. Reduced integration goes hand in hand with Hourglass Control. SOLID185 overcomes volumetric locking via a Mixed u-p formulation which is much more robust. That is pretty much the same approach that COMSOL uses as Henrik pointed out.
Nagi Elabbasi
Veryst Engineering
To be precise ANSYS element SOLID45 overcomes volumetric locking via Reduced Integration not the Enhanced Strains … those are for shear locking. Reduced integration goes hand in hand with Hourglass Control. SOLID185 overcomes volumetric locking via a Mixed u-p formulation which is much more robust. That is pretty much the same approach that COMSOL uses as Henrik pointed out.
Nagi Elabbasi
Veryst Engineering