Source code for woo.tests.energy

# encoding: utf-8
# 2013 © Václav Šmilauer <eudoxos@arcig.cz>

'''
Test some parts of energy conservation in DEM simulations.
'''

import unittest
from minieigen import *
from math import *
from woo._customConverters import *
from woo import utils
from woo.core import *
from woo.dem import *
from woo.pre import *
import woo
import woo.log


[docs]class TestInletsAndOutlets(unittest.TestCase):
[docs] def setUp(self): self.S=Scene(fields=[DemField(gravity=(0,0,0))]) self.S.trackEnergy=True self.mat=woo.utils.defaultMaterial() self.vel=1. self.rad=.1 self.m=self.mat.density*(4/3.)*pi*self.rad**3 self.Ek=.5*self.m*self.vel**2 if 0: woo.log.setLevel('BoxOutlet',woo.log.TRACE) woo.log.setLevel('ConveyorInlet',woo.log.TRACE) woo.log.setLevel('RandomInlet',woo.log.TRACE) woo.log.setLevel('DemField',woo.log.TRACE) woo.log.setLevel('ParticleContainer',woo.log.TRACE)
[docs] def testConveyorInlet(self): 'Energy: conveyor inlet traces kinetic energy' import os S=self.S S.engines=[ ConveyorInlet(maxNum=1,material=self.mat,cellLen=.3,radii=[self.rad],centers=[(0,0,0)],vel=self.vel,node=Node(pos=(0,0,0))), BoxOutlet(inside=True,box=((-1,-1,-1),(1,1,1))) ] S.dt=1. # produce one particle in the first step S.one() #print 100*'#',dict(S.energy) #print 'Number of particles:',len(S.dem.par) self.assertEqual(len(S.dem.par),0) self.assertEqual(S.energy['kinOutlet'],self.Ek) self.assertEqual(S.energy['kinInlet'],-self.Ek) self.assertEqual(S.energy.total(),0.)
[docs] def testRandomInlet(self): 'Energy: random box factory traces kinetic energy' S=self.S S.engines=[ InsertionSortCollider(), BoxInlet(maxNum=1,materials=[self.mat], generator=MinMaxSphereGenerator(dRange=(2*self.rad,2*self.rad)), shooter=AlignedMinMaxShooter(dir=(1,0,0),vRange=(self.vel,self.vel)), box=((-.5,-.5,-.5),(.5,.5,.5)), massRate=0, ), BoxOutlet(inside=True,box=((-1,-1,-1),(1,1,1))), ] S.dt=.05 # produce one particle in the first step S.one() self.assertEqual(S.energy['kinOutlet'],self.Ek) self.assertEqual(S.energy['kinInlet'],-self.Ek) self.assertEqual(S.energy.total(),0.)
[docs]class TestLeapfrog(unittest.TestCase):
[docs] def setUp(self): m=woo.utils.defaultMaterial() self.S=Scene(dtSafety=.9,trackEnergy=True,engines=DemField.minimalEngines(damping=.4), fields=[DemField(gravity=(0,0,-10),par=[Wall.make(0,axis=2,sense=1,mat=m), Sphere.make((0,0,.1),radius=.8,mat=m)])])
[docs] def testGravitySkip(self): 'Energy: DemData.gravitySkip' S=self.S for n in S.dem.nodes: n.dem.gravitySkip=True S.dem.par[-1].vel=(0,0,-1) # so that we hit ground and have dissipation S.run(400,True) self.assertTrue('grav' not in S.energy) self.assertTrue(S.energy['nonviscDamp']!=0.)
[docs] def testDampingSkip(self): 'Energy: DemData.dampingSkip' S=self.S for n in S.dem.nodes: n.dem.dampingSkip=True S.run(400,True) self.assertTrue(S.energy['grav']!=0.) self.assertTrue('nonviscDamp' not in S.energy)