#!/usr/bin/python # -*- coding: UTF-8 no BOM -*- import threading,time,os,subprocess,shlex,string import numpy as np from scipy.optimize import curve_fit from scipy.linalg import svd from optparse import OptionParser import damask scriptID = string.replace('$Id$','\n','\\n') scriptName = scriptID.split()[1][:-3] def execute(cmd,streamIn=None,wd='./'): ''' executes a command in given directory and returns stdout and stderr for optional stdin ''' initialPath=os.getcwd() os.chdir(wd) process = subprocess.Popen(shlex.split(cmd),stdout=subprocess.PIPE,stderr = subprocess.PIPE,stdin=subprocess.PIPE) if streamIn != None: out,error = process.communicate(streamIn.read()) else: out,error = process.communicate() os.chdir(initialPath) return out,error def principalStresses(sigmas): ''' computes principal stresses (i.e. eigenvalues) for a set of Cauchy stresses. sorted in descending order. ''' lambdas=np.zeros(0,'d') for i in xrange(np.shape(sigmas)[1]): eigenvalues = np.linalg.eigvalsh(np.array(sigmas[:,i]).reshape(3,3)) lambdas = np.append(lambdas,np.sort(eigenvalues)[::-1]) #append eigenvalues in descending order lambdas = np.transpose(lambdas.reshape(np.shape(sigmas)[1],3)) return lambdas def stressInvariants(lambdas): ''' computes stress invariants (i.e. eigenvalues) for a set of principal Cauchy stresses. ''' Is=np.zeros(0,'d') for i in xrange(np.shape(lambdas)[1]): I = np.array([lambdas[0,i]+lambdas[1,i]+lambdas[2,i],\ lambdas[0,i]*lambdas[1,i]+lambdas[1,i]*lambdas[2,i]+lambdas[2,i]*lambdas[0,i],\ lambdas[0,i]*lambdas[1,i]*lambdas[2,i]]) Is = np.append(Is,I) Is = Is.reshape(3,np.shape(lambdas)[1]) return Is def formatOutput(n, type='%14.6f'): return ''.join([type for i in xrange(n)]) def get_weight(ndim): #more to do return np.ones(ndim) # --------------------------------------------------------------------------------------------- # isotropic yield surfaces # --------------------------------------------------------------------------------------------- def Tresca(sigmas, sigma0): ''' residuum of Tresca yield criterion (eq. 2.26) ''' lambdas = principalStresses(sigmas) r = np.amax(np.array([abs(lambdas[2,:]-lambdas[1,:]),\ abs(lambdas[1,:]-lambdas[0,:]),\ abs(lambdas[0,:]-lambdas[2,:])]),0) - sigma0 return r.ravel() def vonMises(sigmas, sigma0): ''' residuum of Huber-Mises-Hencky yield criterion (eq. 2.37) ''' return Hosford(sigmas, sigma0, 2.0) def Drucker(sigmas, sigma0, C_D): ''' residuum of Drucker yield criterion (eq. 2.41, F = sigma0) ''' return generalDrucker(sigmas, sigma0, C_D, 1.0) def generalDrucker(sigmas, sigma0, C_D, p): ''' residuum of general Drucker yield criterion (eq. 2.42, F = sigma0) ''' Is = stressInvariants(principalStresses(sigmas)) r = (Is[1,:]**(3.0*p)-C_D*Is[2,:]**(2.0*p)) - sigma0 return r.ravel() def Hosford(sigmas, sigma0, a): ''' residuum of Hershey yield criterion (eq. 2.43, Y = sigma0) ''' lambdas = principalStresses(sigmas) r = (lambdas[2,:]-lambdas[1,:])**a\ + (lambdas[1,:]-lambdas[0,:])**a\ + (lambdas[0,:]-lambdas[2,:])**a\ -2.0*sigma0**a return r.ravel() #more to do # KarafillisAndBoyce # --------------------------------------------------------------------------------------------- # isotropic yield surfaces # --------------------------------------------------------------------------------------------- def Hill1948(sigmas, F,G,H,L,M,N): ''' residuum of Hill 1948 quadratic yield criterion (eq. 2.48) ''' r = F*(sigmas[4]-sigmas[8])**2.0\ + G*(sigmas[8]-sigmas[0])**2.0\ + H*(sigmas[0]-sigmas[4])**2.0\ + 2.0*L* sigmas[1]**2.0\ + 2.0*M* sigmas[2]**2.0\ + 2.0*N* sigmas[5]**2.0\ - 1.0 return r.ravel()/2.0 #more to do # Hill 1979 # Hill 1990,1993 need special stresses to fit def generalHosford(sigmas, sigma0, a): ''' residuum of Hershey yield criterion (eq. 2.104, sigma = sigma0) ''' lambdas = principalStresses(sigmas) r = np.amax(np.array([F*(abs(lambdas[:,1]-lambdas[:,2]))**a,\ G*(abs(lambdas[:,2]-lambdas[:,0]))**a,\ H*(abs(lambdas[:,0]-lambdas[:,1]))**a]),1) - sigma0**a return r.ravel() def Barlat1991(sigmas, sigma0, a): ''' residuum of Hershey yield criterion (eq. 2.104, sigma_e = sigma0) ''' return None def Barlat1994(sigmas, sigma0, a): ''' residuum of Hershey yield criterion (eq. 2.104, sigma_e = sigma0) ''' return None fittingCriteria = { 'Tresca': {'fit' :np.ones(1,'d'),'err':np.inf, 'name' :'Tresca', 'paras':'Initial yield stress:'}, 'vonMises':{'fit' :np.ones(1,'d'),'err':np.inf, 'name' :'Huber-Mises-Hencky(von Mises)', 'paras':'Initial yield stress:'}, 'Hill48' :{'fit' :np.ones(6,'d'),'err':np.inf, 'name' :'Hill1948', 'paras':'Normalized [F, G, H, L, M, N]'}, 'Drucker' :{'fit' :np.ones(2,'d'),'err':np.inf, 'name' :'Drucker', 'paras':'Initial yield stress, C_D:'}, 'worst' :{'err':np.inf}, 'best' :{'err':np.inf} } thresholdParameter = ['totalshear','equivalentStrain'] #--------------------------------------------------------------------------------------------------- class Loadcase(): #--------------------------------------------------------------------------------------------------- ''' Class for generating load cases for the spectral solver ''' # ------------------------------------------------------------------ def __init__(self,finalStrain,incs,time): print('using the random load case generator') self.finalStrain = finalStrain self.incs = incs self.time = time def getLoadcase(self,N=0): defgrad=['*']*9 stress =[0]*9 values=(np.random.random_sample(9)-.5)*self.finalStrain*2 main=np.array([0,4,8]) np.random.shuffle(main) for i in main[:2]: # fill 2 out of 3 main entries defgrad[i]=1.+values[i] stress[i]='*' for off in [[1,3,0],[2,6,0],[5,7,0]]: # fill 3 off-diagonal pairs of defgrad (1 or 2 entries) off=np.array(off) np.random.shuffle(off) for i in off[0:2]: if i != 0: defgrad[i]=values[i] stress[i]='*' return 'f '+' '.join(str(c) for c in defgrad)+\ ' p '+' '.join(str(c) for c in stress)+\ ' incs %s'%self.incs+\ ' time %s'%self.time #--------------------------------------------------------------------------------------------------- class Criterion(object): #--------------------------------------------------------------------------------------------------- ''' Fitting to certain criterion ''' def __init__(self,name='worst'): self.name = name self.results = fittingCriteria if self.name.lower() not in map(str.lower, self.results.keys()): raise Exception('no suitable fitting criterion selected') else: print('fitting to the %s criterion'%name) def fit(self,stress): global fitResults if self.name.lower() == 'tresca': funResidum = Tresca text = '\nCoefficient of Tresca criterion:\nsigma0: '+formatOutput(1) elif self.name.lower() == 'vonmises': funResidum = vonMises text = '\nCoefficient of Huber-Mises-Hencky criterion:\nsigma0: '+formatOutput(1) elif self.name.lower() == 'drucker': funResidum = Drucker text = '\nCoefficient of Drucker criterion:\nsigma0, C_D: '+formatOutput(2) elif self.name.lower() == 'hill48': funResidum = Hill1948 text = '\nCoefficient of Hill1948 criterion:\n[F, G, H, L, M, N]:\n'+formatOutput(6) if fitResults == []: initialguess = fittingCriteria[funResidum.__name__]['fit'] else: initialguess = np.array(fitResults[-1]) weight = get_weight(np.shape(stress)[1]) try: popt, pcov = \ curve_fit(funResidum, stress, np.zeros(np.shape(stress)[1]), initialguess, weight) print (text%popt) fitResults.append(popt.tolist()) except Exception as detail: print detail pass #--------------------------------------------------------------------------------------------------- class myThread (threading.Thread): #--------------------------------------------------------------------------------------------------- ''' Runner class ''' def __init__(self, threadID): threading.Thread.__init__(self) self.threadID = threadID def run(self): s.acquire() conv=converged() s.release() while not conv: doSim(4.,self.name) s.acquire() conv=converged() s.release() def doSim(delay,thread): s.acquire() me=getLoadcase() if not os.path.isfile('%s.load'%me): print('generating loadcase for sim %s from %s'%(me,thread)) f=open('%s.load'%me,'w') f.write(myLoad.getLoadcase(me)) f.close() s.release() else: s.release() s.acquire() if not os.path.isfile('%s_%i.spectralOut'%(options.geometry,me)): print('starting simulation %s from %s'%(me,thread)) s.release() execute('DAMASK_spectral -g %s -l %i'%(options.geometry,me)) else: s.release() s.acquire() if not os.path.isfile('./postProc/%s_%i.txt'%(options.geometry,me)): print('starting post processing for sim %i from %s'%(me,thread)) s.release() try: execute('postResults --cr f,p --co totalshear %s_%i.spectralOut'%(options.geometry,me)) except: execute('postResults --cr f,p %s_%i.spectralOut'%(options.geometry,me)) execute('addCauchy ./postProc/%s_%i.txt'%(options.geometry,me)) execute('addStrainTensors -l -v ./postProc/%s_%i.txt'%(options.geometry,me)) execute('addMises -s Cauchy -e ln(V) ./postProc/%s_%i.txt'%(options.geometry,me)) else: s.release() s.acquire() print('reading values for sim %i from %s'%(me,thread)) s.release() refFile = open('./postProc/%s_%i.txt'%(options.geometry,me)) table = damask.ASCIItable(refFile) table.head_read() if options.fitting =='equivalentStrain': thresholdKey = 'Mises(ln(V))' elif options.fitting =='totalshear': thresholdKey = 'totalshear' s.acquire() for l in [thresholdKey,'1_Cauchy']: if l not in table.labels: print '%s not found'%l s.release() table.data_readArray(['%i_Cauchy'%(i+1) for i in xrange(9)]+[thresholdKey]) line = 0 lines = np.shape(table.data)[0] yieldStress=[None for i in xrange(int(options.yieldValue[2]))] for i,threshold in enumerate(np.linspace(options.yieldValue[0],options.yieldValue[1],options.yieldValue[2])): while line < lines: if table.data[line,9]>= threshold: upper,lower = table.data[line,9],table.data[line-1,9] # values for linear interpolation yieldStress[i] = table.data[line-1,0:9] * (upper-threshold)/(upper-lower) \ + table.data[line ,0:9] * (threshold-lower)/(upper-lower) # linear interpolation of stress values yieldStress[i][1] = (yieldStress[i][1] + yieldStress[i][3])/2.0 yieldStress[i][2] = (yieldStress[i][2] + yieldStress[i][6])/2.0 yieldStress[i][5] = (yieldStress[i][5] + yieldStress[i][7])/2.0 yieldStress[i][3] = yieldStress[i][1] yieldStress[i][6] = yieldStress[i][2] yieldStress[i][7] = yieldStress[i][5] break else: line+=1 s.acquire() global stressAll print('number of yield points of sim %i: %i'%(me,len(yieldStress))) print('starting fitting for sim %i from %s'%(me,thread)) try: for i in xrange(int(options.yieldValue[2])): stressAll[i]=np.append(yieldStress[i]/unitGPa,stressAll[i]) myFit.fit(stressAll[i].reshape(len(stressAll[i])//9,9).transpose()) except Exception: print('could not fit for sim %i from %s'%(me,thread)) s.release() return s.release() def getLoadcase(): global N_simulations N_simulations+=1 return N_simulations def converged(): global N_simulations if N_simulations < options.max: return False else: return True # -------------------------------------------------------------------- # MAIN # -------------------------------------------------------------------- parser = OptionParser(option_class=damask.extendableOption, usage='%prog options [file[s]]', description = """ Performs calculations with various loads on given geometry file and fits yield surface. """, version=string.replace(scriptID,'\n','\\n') ) parser.add_option('-l','--load' , dest='load', type='float', nargs=3, help='load: final strain; increments; time %default', metavar='float int float') parser.add_option('-g','--geometry', dest='geometry', type='string', help='name of the geometry file [%default]', metavar='string') parser.add_option('-c','--criterion', dest='criterion', choices=fittingCriteria.keys(), help='criterion for stopping simulations [%default]', metavar='string') parser.add_option('-f','--fitting', dest='fitting', choices=thresholdParameter, help='yield criterion [%default]', metavar='string') parser.add_option('-y','--yieldvalue', dest='yieldValue', type='float', nargs=3, help='yield points: start; end; count %default', metavar='float float int') parser.add_option('--min', dest='min', type='int', help='minimum number of simulations [%default]', metavar='int') parser.add_option('--max', dest='max', type='int', help='maximum number of iterations [%default]', metavar='int') parser.add_option('-t','--threads', dest='threads', type='int', help='number of parallel executions [%default]', metavar='int') parser.set_defaults(min = 12) parser.set_defaults(max = 30) parser.set_defaults(threads = 4) parser.set_defaults(yieldValue = (0.002,0.004,2)) parser.set_defaults(load = (0.010,100,100.0)) parser.set_defaults(criterion = 'worst') parser.set_defaults(fitting = 'totalshear') parser.set_defaults(geometry = '20grains16x16x16') options = parser.parse_args()[0] if not os.path.isfile(options.geometry+'.geom'): parser.error('geometry file %s.geom not found'%options.geometry) if not os.path.isfile('material.config'): parser.error('material.config file not found') if options.threads<1: parser.error('invalid number of threads %i'%options.threads) if options.min<0: parser.error('invalid minimum number of simulations %i'%options.min) if options.maxoptions.yieldValue[1]: parser.error('invalid yield start (below yield end)') if options.yieldValue[2] != int(options.yieldValue[2]): parser.error('count must be an integer') if not os.path.isfile('numerics.config'): print('numerics.config file not found') if not os.path.isfile('material.config'): print('material.config file not found') unitGPa = 10.e8 N_simulations=0 fitResults = [] s=threading.Semaphore(1) stressAll=[np.zeros(0,'d').reshape(0,0) for i in xrange(int(options.yieldValue[2]))] myLoad = Loadcase(options.load[0],options.load[1],options.load[2]) myFit = Criterion(options.criterion) threads=[] for i in range(options.threads): threads.append(myThread(i)) threads[i].start() for i in range(options.threads): threads[i].join() print 'finished fitting to yield criteria'