# Diff of /trunk/doc/examples/cookbook/example01a.py

trunk/doc/cookbook/onedheatdiff.py revision 2397 by ahallam, Fri Apr 24 04:24:28 2009 UTC trunk/doc/examples/cookbook/example01a.py revision 2980 by artak, Tue Mar 9 03:50:58 2010 UTC
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2  ########################################################  ########################################################
3  #  #
4  # Copyright (c) 2003-2009 by University of Queensland  # Copyright (c) 2009 by University of Queensland
5  # Earth Systems Science Computational Center (ESSCC)  # Earth Systems Science Computational Center (ESSCC)
6  # http://www.uq.edu.au/esscc  # http://www.uq.edu.au/esscc
7  #  #
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11  #  #
12  ########################################################  ########################################################
13
15  Earth Systems Science Computational Center (ESSCC)  Earth Systems Science Computational Center (ESSCC)
16  http://www.uq.edu.au/esscc  http://www.uq.edu.au/esscc
22  """  """
23  Author: Antony Hallam antony.hallam@uqconnect.edu.au  Author: Antony Hallam antony.hallam@uqconnect.edu.au
24  """  """
26    # example01a.py
27    # Model temperature diffusion between two granite blocks of unequal
28    # initial temperature. Solve for total energy in the system.
29
30    #######################################################EXTERNAL MODULES
31  # To solve the problem it is necessary to import the modules we require.  # To solve the problem it is necessary to import the modules we require.
32  from esys.escript import * # This imports everything from the escript library  from esys.escript import * # This imports everything from the escript library
33    from esys.escript.unitsSI import *
34  from esys.escript.linearPDEs import LinearPDE # This defines LinearPDE as LinearPDE  from esys.escript.linearPDEs import LinearPDE # This defines LinearPDE as LinearPDE
35  from esys.finley import Rectangle # This imports the rectangle domain function from finley  from esys.finley import Rectangle # This imports the rectangle domain function from finley
import os #This package is necessary to handle saving our data.
36
37    #################################################ESTABLISHING VARIABLES
38    #Domain related.
39  ##ESTABLISHING VARIABLES  mx = 500*m #meters - model length
40    my = 100*m #meters - model width
41    ndx = 100 # mesh steps in x direction
42    ndy = 1 # mesh steps in y direction - one dimension means one element
43    boundloc = mx/2 # location of boundary between the two blocks
44  #PDE related  #PDE related
45  q=50.e6 #our heat source temperature  rho = 7874. *kg/m**3 #kg/m^{3} density of iron
46  Tref=0. #the starting temperature of our iron bar  cp = 449.*J/(kg*K) # J/Kg.K thermal capacity
47  rho=2.6e6  rhocp = rho*cp
48  eta=0#75.  kappa = 80.*W/m/K   # watts/m.Kthermal conductivity
49  kappa=240.  qH=0 * J/(sec*m**3) # J/(sec.m^{3}) no heat source
50  #Script/Iteration Related  T1=20 * Celsius # initial temperature at Block 1
51  t=0 #our start time, usually zero  T2=2273. * Celsius # initial temperature at Block 2
52  tend=5.#the time we want to end the simulation
53  h=0.05 #size of time step  ################################################ESTABLISHING PARAMETERS
54    t=0 * day  # our start time, usually zero
55  print "Expected Number of Output Files is: ", (tend-t)/h  tend=50 * yr # - time to end simulation
56    outputs = 200 # number of time steps required.
57  i=0 #loop counter  h=(tend-t)/outputs #size of time step
58  save_path = "data/onedheatdiff" #the folder to put our outputs in, leave blank "" for script path - note this folder path must exist to work  #user warning statement
59    print "Expected Number of time outputs is: ", (tend-t)/h
60  #... generate domain ...  i=0 #loop counter
61  rod = Rectangle(l0=0.05,l1=.01,n0=500, n1=1)  #the folder to put our outputs in, leave blank "" for script path
62  # extract finite points  save_path= os.path.join("data","example01")
63  x=rod.getX()  #ensure the dir exists
64  #... open PDE ...  mkDir(save_path, os.path.join(save_path,"tempT"))
65  mypde=LinearPDE(rod)
66    ####################################################DOMAIN CONSTRUCTION
67    blocks = Rectangle(l0=mx,l1=my,n0=ndx, n1=ndy)
68
69    ###############################################ESCRIPT PDE CONSTRUCTION
70    #... open PDE and set coefficients ...
71    mypde=LinearPDE(blocks)
72  mypde.setSymmetryOn()  mypde.setSymmetryOn()
73  mypde.setValue(A=kappa*kronecker(rod),D=rho/h,d=eta,y=eta*Tref)  A=zeros((2,2))
74  # ... set heat source: ....  A[0,0]=kappa
75    mypde.setValue(A=A,D=rhocp/h)
qH=q*whereZero(x[0])
76  # ... set initial temperature ....  # ... set initial temperature ....
77  T=Tref  x=Solution(blocks).getX()
78    T= T1*whereNegative(x[0]-boundloc)+T2*(1-whereNegative(x[0]-boundloc))
79
80  # ... start iteration:  ########################################################START ITERATION
81  while t<=tend:  while t<tend:
82        i+=1        i+=1
83        t+=h        t+=h
84        mypde.setValue(Y=qH+rho/h*T)        mypde.setValue(Y=qH+rhocp/h*T)
85        T=mypde.getSolution()        T=mypde.getSolution()
86        print T        totE=integrate(rhocp*T)
87        saveVTK(os.path.join(save_path,"data%03d.xml") %i,sol=T)        print "time step %s at t=%e days completed. total energy = %e."%(i,t/day,totE)

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