New question #680501 on Yade: https://answers.launchpad.net/yade/+question/680501
Hi There, How Can i impose gravity forces in this code? ------------------- # encoding: utf-8 # This script demonstrates a simple case of drainage simulation using the "2PFV" two-phase model implemented in UnsaturatedEngine. # The script was used to generate the result and supplementary material (video) of [1]. The only difference is the problem size (40k particles in the paper vs. 1k (default) in this version) # [1] Yuan, C., & Chareyre, B. (2017). A pore-scale method for hydromechanical coupling in deformable granular media. Computer Methods in Applied Mechanics and Engineering, 318, 1066-1079. (http://www.sciencedirect.com/science/article/pii/S0045782516307216) import matplotlib; matplotlib.rc('axes',grid=True) from yade import pack import pylab from numpy import * utils.readParamsFromTable(seed=1,num_spheres=1000,compFricDegree = 15.0) from yade.params import table seed=table.seed num_spheres=table.num_spheres# number of spheres compFricDegree = table.compFricDegree # initial contact friction during the confining phase (will be decreased during the REFD compaction process) confiningS=-1e5 ## creat a packing with a specific particle side distribution (PSD) psdSizes,psdCumm=[.599,0.6,0.849,0.85,1.0,1.40],[0.,0.35,0.35,0.70,.70,1.] sp=pack.SpherePack() mn,mx=Vector3(0,0,0),Vector3(10,10,10) sp.makeCloud(minCorner=mn,maxCorner=mx,psdSizes=psdSizes,psdCumm=psdCumm,distributeMass=True,num=num_spheres,seed=seed) ## create material #0, which will be used as default O.materials.append(FrictMat(young=15e7,poisson=.4,frictionAngle=radians(compFricDegree),density=2600,label='spheres')) O.materials.append(FrictMat(young=15e7,poisson=.4,frictionAngle=0,density=0,label='frictionless')) ## create walls around the packing walls=aabbWalls((mn,mx),thickness=0,material='frictionless') wallIds=O.bodies.append(walls) O.bodies.append([utils.sphere(center,rad,material='spheres') for center,rad in sp]) triax=TriaxialStressController( internalCompaction=True, goal1=confiningS, goal2=confiningS, goal3=confiningS, max_vel=10, label="triax" ) newton=NewtonIntegrator(damping=0.4) O.engines=[ ForceResetter(), InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Box_Aabb()]), InteractionLoop( [Ig2_Sphere_Sphere_ScGeom(),Ig2_Box_Sphere_ScGeom()], [Ip2_FrictMat_FrictMat_FrictPhys()], [Law2_ScGeom_FrictPhys_CundallStrack()] ), GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=100,timestepSafetyCoefficient=0.8), triax, newton ] while 1: O.run(1000,True) unb=unbalancedForce() if unb<0.01 and abs(triax.goal1-triax.meanStress)/abs(triax.goal1)<0.001: break ############################# ## REACH NEW EQU. STATE ### ############################# finalFricDegree = 30 # contact friction during the deviatoric loading #We move to deviatoric loading, let us turn internal compaction off to keep particles sizes constant triax.internalCompaction=False # Change contact friction (remember that decreasing it would generate instantaneous instabilities) setContactFriction(radians(finalFricDegree)) while 1: O.run(1000,True) unb=unbalancedForce() if unb<0.001 and abs(triax.goal1-triax.meanStress)/abs(triax.goal1)<0.001: break triax.depth0=triax.depth triax.height0=triax.height triax.width0=triax.width O.save('1kPacking.yade') #save the packing, which can be reloaded later. O.run(1000,True) ei0=-triax.strain[0];ei1=-triax.strain[1];ei2=-triax.strain[2] si0=-triax.stress(0)[0];si1=-triax.stress(2)[1];si2=-triax.stress(4)[2] from yade import plot O.engines=O.engines+[PyRunner(iterPeriod=20,command='history()',dead=1,label='recorder')] def history(): plot.addData(e11=-triax.strain[0]-ei0, e22=-triax.strain[1]-ei1, e33=-triax.strain[2]-ei2, s11=-triax.stress(0)[0]-si0, s22=-triax.stress(2)[1]-si1, s33=-triax.stress(4)[2]-si2, pc=-unsat.bndCondValue[2], sw=unsat.getSaturation(False), i=O.iter ) plot.plots={'pc':('sw',None,'e22')} plot.plot() ####################################################### ## Drainage Test under oedometer conditions ### ####################################################### ##oedometer conditions triax.stressMask=2 triax.goal1=triax.goal3=0 goalTop=triax.stress(3)[1] triax.goal2=goalTop triax.wall_bottom_activated=0 recorder.dead=0 ##Instantiate a two-phase engine unsat=TwoPhaseFlowEngine() meanDiameter=(O.bodies[-1].shape.radius + O.bodies[6].shape.radius) / 2. ##set boundary conditions, the drainage is controlled by decreasing W-phase pressure and keeping NW-phase pressure constant unsat.bndCondIsPressure=[0,0,1,1,0,0] unsat.bndCondValue=[0,0,-1e8,0,0,0] unsat.isPhaseTrapped=True #the W-phase can be disconnected from its reservoir unsat.initialization() unsat.surfaceTension = 10 ##start invasion, the data of normalized pc-sw-strain will be written into pcSwStrain.txt file=open('pcSwStrain.txt',"w") for pg in arange(1.0e-5,15.0,0.1): #increase gaz pressure at the top boundary unsat.bndCondValue=[0,0,(-1.0)*pg*unsat.surfaceTension/meanDiameter,0,0,0] #compute the evolution of interfaces unsat.invasion() #save the phases distribution in vtk format, to be displayed by paraview unsat.savePhaseVtk("./") #compute and apply the capillary forces on each particle unsat.computeCapillaryForce() for b in O.bodies: O.forces.setPermF(b.id, unsat.fluidForce(b.id)) #reac while 1: O.run(1000,True) unb=unbalancedForce() if unb<0.01: break file.write(str(pg)+" "+str(unsat.getSaturation(False))+" "+str(triax.strain[1]-ei1)+"\n") file.close() -- 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 : [email protected] Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
