boundary thickness is 0.001 by default in FlowEngine
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Yade |
Fix Released
|
Low
|
Bruno Chareyre |
Bug Description
Hi,
I want to get the pore pressure of a saturated soil sample in an undrained triaxial test when the sample volume is decreasing.
...
TriaxialStressC
...
triax.goal1 = 35000
triax.goal2 = 35000
triax.goal3 = 70000
triax.
...
flow.viscosity = 1.3e-3
flow.fluidBulk
flow.bndCondVa
flow.bndCondIs
...
For one of my simulations a decrease of ca. 1,8 % in porosity (=-dV/V) is obtained. When I calculate corresponding pressure increase I get
dp = K*(-dV/V) = 2e9*0.018 = 36000000 Pa
But the output from PFV shows maximum average pressures around of 16 Pa (not MPa!). As long as I use SI units the output of flow.averagePre
So is there a problem in the code or did I miss something in the compressibility option of PFV?
regards,
christian
###additional info:
I double-checked my script and did not see anything wrong. So I think it is on C++ side. So I was going on testing PFV method:
I also tested a drained situation with incompressible fluid. The porosity is decreasing due to a triggered collapse of the grain structure, but the pore pressure gets negative (see attachment).
So I think it is a bug in pressure calculation of PFV method.
Changed in yade: | |
importance: | Undecided → Low |
status: | New → Confirmed |
assignee: | nobody → Bruno Chareyre (bruno-chareyre) |
summary: |
- problem with pressure calculation in PFV cells + boundary thickness is 0.001 by default in FlowEngine |
Hi Christian,
Could you please show how to reproduce this in a simple case?
I didn't find any results like what you report before.