added fixed T flame example

Cantera/python/examples/flames/fixed_T_flame.py

@@ -0,0 +1,147 @@
+#
+# FIXED_T_FLAME - A burner-stabilized, premixed methane/air flat flame
+#                 with multicomponent transport properties and a specified
+#                 temperature profile
+#
+from Cantera import *
+from Cantera.OneD import *
+from Cantera.OneD.BurnerFlame import BurnerFlame
+from string import atof
+
+
+# read temperature vs. position data from a file.
+# The file is assumed to have one z, T pair per line, separated by a comma.
+
+def getTempData(filename):
+    # open the file containing the temperature data for reading
+    f = open(filename)
+    z = []
+    t = []
+    lines = f.readlines()
+
+    # check for unix/Windows/Mac line ending problems
+    if len(lines) == 1:
+        print 'Warning: only one line found. Possible text file line-ending'
+        print 'problem?'
+        print 'The one line found is: ',lines[0]
+
+        
+    for line in lines:
+        if line[0] == '#':   # use '#' as the comment character
+            pass
+        else:
+            try:
+                zval, tval = line.split(',')
+                z.append(atof(zval))
+                t.append(atof(tval))
+            except:
+                pass
+    print 'read',len(z),'temperature values.'
+    f.close()
+    
+    # convert z values into non-dimensional relative positions.
+    n = len(z)
+    zmax = z[n-1]
+    for i in range(n):
+        z[i] = z[i]/zmax
+        
+    return [z,t]
+
+
+
+################################################################
+#
+# parameter values
+#
+p          =   OneAtm               # pressure
+tburner    =   373.7                # burner temperature
+mdot       =   0.04                 # kg/m^2/s
+
+comp       =  'CH4:0.65, O2:1, N2:3.76'  # premixed gas composition
+
+# The solution domain is chosen to be 1 cm, and a point very near the
+# downstream boundary is added to help with the zero-gradient boundary
+# condition at this boundary.
+initial_grid = [0.0, 0.0025, 0.005, 0.0075, 0.0099, 0.01] # m
+
+tol_ss    = [1.0e-5, 1.0e-9]        # [rtol atol] for steady-state
+                                    # problem
+tol_ts    = [1.0e-5, 1.0e-4]        # [rtol atol] for time stepping
+
+loglevel  = 1                       # amount of diagnostic output (0
+                                    # to 5)
+				    
+refine_grid = 1                     # 1 to enable refinement, 0 to
+                                    # disable 				   
+
+
+################ create the gas object ########################
+#
+# This object will be used to evaluate all thermodynamic, kinetic, and
+# transport properties. It is created with two transport managers, to
+# enable switching from mixture-averaged to multicomponent transport
+# on the last solution.
+gas = GRI30('Mix')
+gas.addTransportModel('Multi')
+
+# set its state to that of the unburned gas at the burner
+gas.setState_TPX(tburner, p, comp)
+
+# create the BurnerFlame object.
+f = BurnerFlame(gas = gas, grid = initial_grid)
+
+# set the properties at the burner
+f.burner.set(massflux = mdot, mole_fractions = comp, temperature = tburner)
+
+# read in the fixed temperature profile
+[zloc, tvalues] = getTempData('tdata.csv')
+
+# set the temperature profile to the values read in
+f.flame.setFixedTempProfile(zloc, tvalues)
+
+f.set(tol = tol_ss, tol_time = tol_ts)
+
+# show the initial estimate for the solution
+f.showSolution()
+
+# don't solve the energy equation
+f.set(energy = 'off')
+
+# first solve the flame with mixture-averaged transport properties
+f.setRefineCriteria(ratio = 3.0, slope = 0.3, curve = 1)
+f.setMaxJacAge(50, 50)
+f.setTimeStep(1.0e-5, [1, 2, 5, 10, 20])
+
+f.solve(loglevel, refine_grid)
+f.save('ch4_flame_fixed_T.xml','mixav',
+       'solution with mixture-averaged transport')
+
+gas.switchTransportModel('Multi')
+f.flame.setTransportModel(gas)
+f.setRefineCriteria(ratio = 3.0, slope = 0.1, curve = 0.2)
+f.solve(loglevel, refine_grid)
+f.save('ch4_flame_fixed_T.xml','multi',
+       'solution with  multicomponent transport')
+
+# write the velocity, temperature, density, and mole fractions to a CSV file
+z = f.flame.grid()
+T = f.T()
+u = f.u()
+V = f.V()
+fcsv = open('flame_fixed_T.csv','w')
+writeCSV(fcsv, ['z (m)', 'u (m/s)', 'V (1/s)', 'T (K)', 'rho (kg/m3)']
+         + list(gas.speciesNames()))
+for n in range(f.flame.nPoints()):
+    f.setGasState(n)
+    writeCSV(fcsv, [z[n], u[n], V[n], T[n], gas.density()]
+             +list(gas.moleFractions()))
+fcsv.close()
+
+print 'solution saved to flame_fixed_T.csv'
+
+f.showStats()
+
+
+
+
+

Cantera/python/examples/flames/tdata.csv

@@ -0,0 +1,74 @@
+#
+# This data file lists temperature vs. height values for a burner-stabilized flame.
+# This file is used by example 'fixed_T_flame.py'.  
+#
+0,  373.7
+0.00015625,  465.4070428
+0.000234375,  510.4311676
+0.000390625,  599.5552837
+0.00046875,  643.8342938
+0.000507813,  665.9335545
+0.000546875,  688.0122338
+0.000625,  732.1284327
+0.000664062,  754.1744755
+0.000703125,  776.2170662
+0.000742188,  798.2588757
+0.00078125,  820.3020011
+0.000820313,  842.348001
+0.000859375,  864.3979228
+0.000898437,  886.4523159
+0.0009375,  908.5112198
+0.001015625,  952.6396629
+0.001054688,  974.7018199
+0.00109375,  996.7515831
+0.001132813,  1018.777651
+0.001171875,  1040.765863
+0.001210938,  1062.69948
+0.00125,  1084.558639
+0.001289062,  1106.320078
+0.001328125,  1127.956918
+0.001367187,  1149.438472
+0.00140625,  1170.730129
+0.001445313,  1191.793309
+0.001484375,  1212.585506
+0.001523438,  1233.060477
+0.0015625,  1253.168589
+0.001601563,  1272.857384
+0.001640625,  1292.072391
+0.00171875,  1328.859767
+0.001757812,  1346.323998
+0.001796875,  1363.101361
+0.001835937,  1379.147594
+0.001875,  1394.425274
+0.001914063,  1408.905834
+0.001953125,  1422.569115
+0.001992188,  1435.40408
+0.00203125,  1447.410648
+0.002070313,  1458.597668
+0.002109375,  1468.982722
+0.002148438,  1478.590978
+0.0021875,  1487.453914
+0.002226563,  1495.607879
+0.002265625,  1503.092709
+0.002304688,  1509.950449
+0.00234375,  1516.224147
+0.002382813,  1521.956853
+0.002421875,  1527.19079
+0.002460938,  1531.966722
+0.0025,  1536.32348
+0.002578125,  1543.891739
+0.00265625,  1550.203579
+0.002734375,  1555.480771
+0.0028125,  1559.908135
+0.002890625,  1563.637879
+0.00296875,  1566.794144
+0.003046875,  1569.477867
+0.003125,  1571.77099
+0.00328125,  1575.385829
+0.0034375,  1578.108169
+0.00359375,  1580.194856
+0.00375,  1581.820666
+0.00390625,  1583.106578
+0.0087,  1589.51315
+0.01,  1589.578955
+