Hi Prabhat, To answer your question: You probably see a warning in your output file, """" WARNING! At least one clump is initialized with a position out of the box domain you specified. It is found at 0.378, 0, 0.076383 (this message only shows one such example). This simulation is unlikely to go as planned. """ This is the problem. It appears that the points you sampled live in x∈[0, 0.4], but the x range of your simulation world is defined as something like [-0.25, 0.25]. This will make the particles to be initialized in unexpected locations, cause large initial penetrations, and then destabilize the simulation. I fixed the world size definition, and it seems to fix the problem. The extremely fine step size you are using is not necessary: The physics in this simulation is simple.
By the way, in the upcoming paper about DEME <https://arxiv.org/abs/2311.04648>, we will include a Goldenberg test example, and provide the associated demo script. If you want, we can let you know when it is officially published. Thank you, Ruochun On Tuesday, March 26, 2024 at 1:41:58 AM UTC+8 [email protected] wrote: > Hello everyone, > > I have been trying to replicate the 2D Goldenberg et al experiment > <https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.89.084302> in > DEME. It was replicated as a validation study for Chrono::GPU (as described > in the 2021 paper <https://doi.org/10.3390/pr9101813>), so I figured it > could be easily done in DEME too. However, I am having some issues with > generating particles and having them settle under gravity. I have been > using a nested for loop to generate the initial positions of particles and > while I don't have any issues with the generation of positions (see > attached paraview screenshot), I encounter the excessive velocity run-time > error while settling the particles under gravity. I have tried to decrease > the step size, increase the box domain dimensions to eliminate boundary > effects, relax the physics (decrease the Young's modulus of the terrain), > and increased the initial safety distance of the particles to no avail. > > I have attached my code to this message and I have been modifying the 2D > ball drop demo. > > Thanks and regards, > Prabhat > -- You received this message because you are subscribed to the Google Groups "ProjectChrono" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/projectchrono/934f2ef4-1e51-4921-8909-2ee0ac10eae6n%40googlegroups.com.
