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a wrong unit system used in verification test 201?

a wrong unit system used in verification test 201?

a wrong unit system used in verification test 201?

(OP)
Hi,
VM201 is the Verification Test of Rubber Cylinder Pressed Between Two Plates.
I noticed the VM201 used a strange unit system where length unit is m, force unit is N but Young's modulus unit is MPa.

/VERIFY,VM201
...
R = 0.2                        ! RADIUS OF CYLINDER
!!no unit is given in its list, but meter unit is used in the description of this verification example.
...
MP,EX,1,2.82                   ! YOUNG'S MODULUS [MPA]
MP,NUXY,1,0.49967              ! POISSON'S RATIO

Is there anything wrong with the unit system used in VM201?

Thanks,

Tsukuba

RE: a wrong unit system used in verification test 201?

No, there is nothing wrong. The stresses will be in MPa, the units of force are Newtons. This is a displacement controlled analysis, if it was force controlled, you could use any particular order of modulus (2.82 or 2.82E9 etc.) and get the same stress (but the displacement would change).

RE: a wrong unit system used in verification test 201?

(OP)
Thanks Drej,

I am sorry I cannot get what you said. I think the key point is the displacement controlled analysis. I want to know why the units of force are Newtons in a displacement controlled analysis if the stresses are in MPa.

In fact, I think the units of force are MegNewtons, because meters, MegNewtons and MPa are consistent unit system. If the force are in Newtons, then the lengths should be in millimeters.

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