New question #677829 on Yade: https://answers.launchpad.net/yade/+question/677829
Hi Yade developers & users, I'm a beginner in Yade who just tried this DEM code about 1 month ago. The version of Yade I installed is 2018.02b version. I am currently trying to learn the python codes from tutorial example of "periodic triaxial test" obtained from Yade website. However, when I try to run the script for periodic triaxial test tutorial example, the following error message pop up: ================================================================================================== FATAL /build/yade-fDuCoe/yade-2018.02b/pkg/common/InsertionSortCollider.cpp:495 spatialOverlapPeri: Body #930 spans over half of the cell size 0.167286 (axis=2, see flag allowBiggerThanPeriod) FATAL /build/yade-fDuCoe/yade-2018.02b/core/ThreadRunner.cpp:30 run: Exception occured: /build/yade-fDuCoe/yade-2018.02b/pkg/common/InsertionSortCollider.cpp: Body larger than half of the cell size encountered. ===================================================================================================== I hope someone can advise me how to solve this problem. Thanks in advance, Nicholas ***** the script for periodic triaxial test in tutorial example is as follow: ============================================================================================= # encoding: utf-8 # periodic triaxial test simulation # # The initial packing is either # # 1. random cloud with uniform distribution, or # 2. cloud with specified granulometry (radii and percentages), or # 3. cloud of clumps, i.e. rigid aggregates of several particles # # The triaxial consists of 2 stages: # # 1. isotropic compaction, until sigmaIso is reached in all directions; # this stage is ended by calling compactionFinished() # 2. constant-strain deformation along the z-axis, while maintaining # constant stress (sigmaIso) laterally; this stage is ended by calling # triaxFinished() # # Controlling of strain and stresses is performed via PeriTriaxController, # of which parameters determine type of control and also stability # condition (maxUnbalanced) so that the packing is considered stabilized # and the stage is done. # sigmaIso=-1e5 #import matplotlib #matplotlib.use('Agg') # generate loose packing from yade import pack, qt, plot O.periodic=True sp=pack.SpherePack() if 0: ## uniform distribution sp.makeCloud((0,0,0),(2,2,2),rMean=.1,rRelFuzz=.3,periodic=True) else: ## create packing from clumps # configuration of one clump c1=pack.SpherePack([((0,0,0),.03333),((.03,0,0),.017),((0,.03,0),.017)]) # make cloud using the configuration c1 (there could c2, c3, ...; selection between them would be random) sp.makeClumpCloud((0,0,0),(2,2,2),[c1],periodic=True,num=500) # setup periodic boundary, insert the packing sp.toSimulation() O.engines=[ ForceResetter(), InsertionSortCollider([Bo1_Sphere_Aabb()]), InteractionLoop( [Ig2_Sphere_Sphere_ScGeom()], [Ip2_FrictMat_FrictMat_FrictPhys()], [Law2_ScGeom_FrictPhys_CundallStrack()] ), PeriTriaxController(label='triax', # specify target values and whether they are strains or stresses goal=(sigmaIso,sigmaIso,sigmaIso),stressMask=7, # type of servo-control dynCell=True,maxStrainRate=(10,10,10), # wait until the unbalanced force goes below this value maxUnbalanced=.1,relStressTol=1e-3, # call this function when goal is reached and the packing is stable doneHook='compactionFinished()' ), NewtonIntegrator(damping=.2), PyRunner(command='addPlotData()',iterPeriod=100), ] O.dt=.5*PWaveTimeStep() def addPlotData(): plot.addData(unbalanced=unbalancedForce(),i=O.iter, sxx=triax.stress[0],syy=triax.stress[1],szz=triax.stress[2], exx=triax.strain[0],eyy=triax.strain[1],ezz=triax.strain[2], # save all available energy data Etot=O.energy.total(),**O.energy ) # enable energy tracking in the code O.trackEnergy=True # define what to plot plot.plots={'i':('unbalanced',),'i ':('sxx','syy','szz'),' i':('exx','eyy','ezz'), # energy plot ' i ':(O.energy.keys,None,'Etot'), } # show the plot plot.plot() def compactionFinished(): # set the current cell configuration to be the reference one O.cell.trsf=Matrix3.Identity # change control type: keep constant confinement in x,y, 20% compression in z triax.goal=(sigmaIso,sigmaIso,-.2) triax.stressMask=3 # allow faster deformation along x,y to better maintain stresses triax.maxStrainRate=(1.,1.,.1) # next time, call triaxFinished instead of compactionFinished triax.doneHook='triaxFinished()' # do not wait for stabilization before calling triaxFinished triax.maxUnbalanced=10 def triaxFinished(): print 'Finished' O.pause() ======================================================================================== -- You received this question notification because your team yade-users is an answer contact for Yade. _______________________________________________ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp