Reply To: Hydrostatic fluid elements: iterative solution

[Janne]

Hello Erik,

I appreciate your prompt response. The cavity volume/pressure is coupled to the deformation of the solid, which is inherently a nonlinear relationship. What I have been able to find is this--you can run the analysis using:

1) Geometrically linear analysis

2) Geometrically linear analysis with NROPT,full (newton-raphson iteration)

3) Geometrically nonlinear analysis with NLGEOM,on (also uses newton-raphson iteration)

Obviously 3) is the most accurate because it includes large deflections. If one has small deformations, 2) is suggested. But what I am interested is how is the cavity volume/pressure solved in case 1) because this is 99.9% accurate with analytical exact methods (they don't iterate). 1) and 2) almost equal in terms of cavity volume/pressure and structural deformations and stresses (at least in my case study). 

In case 1) does ANSYS have some initial guess of the volume change and uses that or what?