[Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread wangxiaoliang
New question #210907 on Yade: https://answers.launchpad.net/yade/+question/210907 In real triaxial compression of granular sand, relative density is usually a key parameter to control the initial state of the sample. I want to simulate the triaxial compression using yade. topic here is all abo

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Luc Scholtès
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Status: Open => Answered Luc Scholtès proposed the following answer: Hello Wangxiaoliang, If I understand well, you are able to generate your samples at different porosities but you have some troubles when

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Christian Jakob
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Christian Jakob proposed the following answer: > and anybody has advanced method to generate numerical sample to model real granular sand? Hi wangxiaoliang, I also want to simulate a sand with DEM. So our inter

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread wangxiaoliang
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Status: Answered => Open wangxiaoliang is still having a problem: thanks, luc. I have read the paper many times. I am simulating a sand of relative density of 64%, a bit dense sample. I have calibrated like

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread wangxiaoliang
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 wangxiaoliang gave more information on the question: thanks Christian, I never used clump particles, I just want to use a resistance model to model the complex shape of particles. 1), what do you mean by instabi

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread wangxiaoliang
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 wangxiaoliang gave more information on the question: In plassiard's paper, he used radius-expansion method. there is one sentence in his paper "With it, the desired porosity which corresponds to the porosity of

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Anton Gladky
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Status: Open => Answered Anton Gladky proposed the following answer: Hi, esys-particle team [1] has a tool for generating relatively dense, non-stress packings of spheres "python-demgengeo" [2]. The result

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Christian Jakob
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Christian Jakob posted a new comment: > 1), what do you mean by instabilities? > 2), I the consolidation process, which friction do you use? 1.) model explodes sometimes (I have high shear modulus of 3.2e10) 2.)

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Chiara Modenese
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Chiara Modenese proposed the following answer: On 11 Oct 2012, at 08:56, wangxiaoliang wrote: > Actually, I am talking about the sample controlling parameters, somebody > use porosity, somebody use relative den

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Luc Scholtès
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Luc Scholtès proposed the following answer: ""With it, the desired porosity which corresponds to the porosity of the real specimen n = 0.40 was reached" I never understand this, n in the real specimen is 0.40, b

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Chareyre
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Chareyre proposed the following answer: I agree with Luc: the topic should be "What am I doing wrong with moment law?". The rest is useless at this point. The recently added triax-cohesive.py includes rolling fr

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Chiara Modenese
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Chiara Modenese proposed the following answer: On 11 Oct 2012, at 11:46, Chareyre wrote: > - In 2, there is no need to "calm". If it goes very dynamic it's because the parameters of the growth are not well choo

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Christian Jakob
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Christian Jakob posted a new comment: > @Christian: If you use very _high_ stiffness with the non-linear model you > need to be careful to choose the right parameters > for the expansion method > as Bruno sugge

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Chiara Modenese
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Chiara Modenese proposed the following answer: On 11 Oct 2012, at 14:11, Christian Jakob wrote: > Question #210907 on Yade changed: > https://answers.launchpad.net/yade/+question/210907 > > Christian Jakob pos

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Chareyre
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Chareyre posted a new comment: >I generate the particles in a very loose state and then I apply compression Then the microstructure is heterogeneous, with a gradient of porosity and fabric from the contour to th

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread wangxiaoliang
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 wangxiaoliang posted a new comment: >@ luc #9: I guess this should be the title of your question? I also guess that >you are using Law2_ScGeom6D_CohFrictPhys_CohesionMoment. Am I right? Yes you are right. I know

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Luc Scholtès
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Luc Scholtès proposed the following answer: OK, so the problem is more general that just "rolling moment related" as I supposed it was... Maybe you should open questions for each problem because it is difficult

Re: [Yade-users] [Question #210907]: on sample preparation of real granula materials

2012-10-11 Thread Chiara Modenese
Question #210907 on Yade changed: https://answers.launchpad.net/yade/+question/210907 Chiara Modenese proposed the following answer: On 11 Oct 2012, at 15:11, Chareyre wrote: > Question #210907 on Yade changed: > https://answers.launchpad.net/yade/+question/210907 > > Chareyre posted a new comm