Error with Paraview outputs

[laurenboag1]

Hello,

I am trying to output the density evolution of the cantilever for both bone and concrete. However neither are outputting the expected solutions.

I have set the minimum bound to the corresponding reference density for each case but almost all the material is above this which is unexpected and means little to no optimisation is visible.

For bone I have used the following parameters. I converted the stated ref density from 1 g/cm3 to 0.001g/mm3  and c to 0.004. I have also tried rho = 1 and c = 0.4, as well as rho = 0.001 and c= 0.4. None of them have yielded the correct result (ie anything similar to the Waffenschmidt paper)

Paraview for t = 40s, for rho = 0.001 and c= 0.004, not the expected result.

For concrete I have applied a load of 100,000,000 N and the following parameters. The density values are well below the reference density so I know this is wrong.

However the paraview view at time 30 seconds looks like this.

Any advice on what I have done wrong and why the optimisation is not showing correctly would be greatly appreciated.

Kind regards,

Lauren

[Karol Lewandowski]

Hi,

As you might remember from the parameter study neither the reference density nor c parameter controls the level of the density at the equilibrium. The density is mainly driven with psi_ref parameter.

[laurenboag1]

Yes, I understand, just wanted to double check as the units are cm instead of mm.

The psi ref values are prescribed in the literature therefore I am unsure why the solution is not as expected.

Any suggestions as to how I can resolve the issue?

Lauren

[laurenboag1]

Hi,

When using the parameters below, the density is evolving to values to less than ref density at the final time step. 

This makes does not make sense. I am wondering if this is due to an inconsistency in the units of rho, or if the force being applied is not large enough?

E = 3800 N/mm2

v = 0.3

c = 0.4 g/cm3

rho ref = 1 g/cm3

psi ref = 0.01 N/mm2

I understand the the evolution is driven by the choice of psi value however as this is prescribed in the literature and the units are consistent with the young's modulus I do not see how this could be changed.

I have tried playing with parameters but have had no success.

The result at the final time step is always a consistent density across the entire structure, and a density value below the reference.

I would appreciate any suggestions.

Kind regards, 

Lauren