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from esys.escript import * |
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|
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class TransportPDE(object): |
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def __init__(self,domain,num_equations=1,theta=0.,dt_max=-1.,trace=True): |
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self.__domain=domain |
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self.__num_equations=num_equations |
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self.__theta=theta |
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self.__dt_max=dt_max |
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self.__transport_problem=None |
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self.__trace=trace |
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self.__matrix_type=0 |
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def trace(self,text): |
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if self.__trace: print text |
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|
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def getDomain(self): |
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return self.__domain |
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def getTheta(self): |
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return self.__theta |
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def getDt_max(self): |
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return self.__dt_max |
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def getNumEquations(self): |
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return self.__num_equations |
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def reduced(self): |
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return False |
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def getFunctionSpace(self): |
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if self.reduced(): |
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return ReducedSolution(self.getDomain()) |
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else: |
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return Solution(self.getDomain()) |
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|
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|
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def __getNewTransportProblem(self): |
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""" |
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returns an instance of a new operator |
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""" |
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self.trace("New Transport problem is allocated.") |
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return self.getDomain().newTransportProblem( \ |
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self.getTheta(), |
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self.getDt_max(), |
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self.getNumEquations(), \ |
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self.getFunctionSpace(), \ |
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self.__matrix_type) |
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|
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def setValue(self,M=Data(),A=Data(),B=Data(),C=Data(),D=Data(),X=Data(),Y=Data(), |
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d=Data(),y=Data(),d_contact=Data(),y_contact=Data()): |
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self.__transport_problem=self.__getNewTransportProblem() |
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if self.getNumEquations() ==1 : |
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self.__source=Data(0.0,(),self.getFunctionSpace()) |
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else: |
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self.__source=Data(0.0,(self.getNumEquations(),),self.getFunctionSpace()) |
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self.getDomain().addPDEToTransportProblem( |
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self.__transport_problem, |
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self.__source, |
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M,A,B,C,D,X,Y,d,y,d_contact,y_contact) |
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|
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def setInitialSolution(self,u): |
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self.__transport_problem.setInitialValue(interpolate(u,self.getFunctionSpace())) |
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def solve(self,dt): |
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return self.__transport_problem.solve(self.__source,dt,{}) |
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from esys.finley import Rectangle |
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|
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dom=Rectangle(20,20) |
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fc=TransportPDE(dom,num_equations=1,theta=0.0,dt_max=0.) |
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fc.setValue(M=Scalar(1.,Function(dom)),C=Scalar(1.,Function(dom))*[-1.,0]) |
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x=dom.getX() |
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x_0=[0.3,0.3] |
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sigma=0.08 |
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u=1. |
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for i in range(dom.getDim()): |
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u=u*exp(-(x[i]-x_0[i])**2/sigma**2) |
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u/=Lsup(u) |
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|
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u=whereNonPositive(abs(x[0]-0.3)-0.2)*whereNonPositive(abs(x[1]-0.5)-0.2) |
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c=0 |
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saveVTK("u.%s.xml"%c,u=u) |
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fc.setInitialSolution(u) |
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|
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dt=2.5e-2 |
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t=0. |
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while t<15*dt: |
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print "time step t=",t+dt |
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u=fc.solve(dt) |
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print "range u",inf(u),sup(u) |
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c+=1 |
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saveVTK("u.%s.xml"%c,u=u) |
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t+=dt |