PFC - Energy Balance

PFC
1

Hello,

I am analyzing the energy balance in a triaxial compression simulation using the Linear Parallel Bond Model in PFC. I am tracking the boundary work (input energy), parallel bond strain energy, contact strain energy, slip energy, damping energy, and kinetic energy.
When I subtract all these energy components from the boundary work, I still obtain a relatively large residual. I expected the residual to be very small if energy is conserved, especially under quasi-static loading.

My main questions are:
Is there a way to estimate the energy associated with numerical integration or numerical dissipation in PFC, or is this quantity simply unavailable?
Are there any other energy components that I should include in the energy balance for the LPBM?
What are the most common reasons for a large energy residual, and how can it be reduced?

I would appreciate any insights! Thank you!

2

Dear AlaaAbdallah, Thank you for your use of PFC. You ask about tracking energy in PFC. I attach here a memo that describe energy tracking for a rock-cutting model. The quantities are given and defined in Table 3, and the energies do balance as shown in Fig. 27. For a PFC model, all energy quantities are known, and the energies should balance. I am not aware of energy being associated with numerical integration or numerical dissipation — not sure what you mean by dissipation.

rcSupport9.1c.pdf (8.0 MB)