Hi cbrn,
Thanks for the inputs.
This is the part of the code dealing with material model specification
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,PRXY,1,,.49
TBFT,EADD,1,UNIA,file_UNIA_1.exp
TBFT,FADD,1,HYPER,MOON,3
TBFT,SOLVE,1,HYPER,MOON,3,1
TBFT,FSET,1,HYPER,MOON,3
MPTEMP,,,,,,,,
MPTEMP,1,0...
Hi,
Another question that I have regarding Mooney-Rivlin model fitting to experimental data in Ansys:
Once we fit the Mooney-Rivlin (or any other model) to the stress-strain data in Ansys, is that the final material defining step. Or should we also provide a value of elastic modulus. I have...
Hi cbrn
I understand what you are saying. stress=E*strain is not valid for non-linear problem. But then, stress is related to strain through a constitutive matrix which would consist of hyperelastic material constants determined using a non-linear material model. So, basically strains would be...
Hi cbrn
I have been thinking about this and it does seem likely that uniaxial test data is the cause of the problem. I do have large deflection analysis turned on.
However, another question that plagues me here is:
what happens when we take a linear material modulus corresponding to uniaxial...
I am trying to model a hyperelastic material using shell181 element in Ansys. I provide uniaxial stress-strain test data and fit a Mooney-Rivlin model to it. The fit is very good. However, in the final solution, I find that the material stress and strain do not relate as per the defined...
Hi Saikin,
I had posted parts of the code above. The sections and real constants were assigned to the required areas. I had made an error while defining the density in one of the parts (i guess while defining sections). The density units were inconsistent (I have corrected it in the code pasted...
material 2 is for another part of the geometry. That mightnot be relevant here. However, I managed to solve the problem, the results are same as expected (from use of real and sections).
Thanks for the help. I appreciate it.
Thanks again
I am posting parts of the code that deal with specifying real and sections:
For the sections option:
et,1,shell181
KEYOPT,1,1,0
KEYOPT,1,3,2
KEYOPT,1,8,0
KEYOPT,1,9,0
KEYOPT,1,10,0
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,EX,1,,7e3
MPDATA,PRXY,1,,0.4
MPTEMP,,,,,,,,
MPTEMP,1,0...
Hi,
I have a thin structure which I model using the shell181 element in Ansys. As long as I provide the thickness of the structure using the 'real' definition (just one layer), the results are fine. When I try to model the same structure as a composite using 2 layered sections, the results are...