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cantera/samples/python/tut1.py
Ray Speth 2528df0f75 Reorganized source tree structure 
These changes make it unnecessary to copy header files around during
the build process, which tends to confuse IDEs and debuggers. The
headers which comprise Cantera's external C++ interface are now in
the 'include' directory.

All of the samples and demos are now in the 'samples' subdirectory.
2012-02-12 02:27:14 +00:00

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#################################
print """
Tutorial 1: Getting started
"""
##################################
# Put this statement at the top of each Python script to import the
# most commonly-used parts of Cantera:
from Cantera import *
# The first thing you need is an object representing some phase of
# matter. We'll create here a gas mixture:
gas1 = GRI30()
# To view the state of the mixture, just print it:
print gas1
# You should see something like this:
#
# temperature 300 K
# pressure 101325 Pa
# density 0.081889 kg/m^3
# mean mol. weight 2.01588 amu
# 1 kg 1 kmol
# ----------- ------------
# enthalpy 26470.1 5.336e+04 J
# internal energy -1.21088e+06 -2.441e+06 J
# entropy 64914 1.309e+05 J/K
# Gibbs function -1.94477e+07 -3.92e+07 J
# heat capacity c_p 14311.8 2.885e+04 J/K
# heat capacity c_v 10187.3 2.054e+04 J/K
# X Y
# ------------- ------------
# H2 1.000000e+00 1.000000e+00
# H 0.000000e+00 0.000000e+00
# O 0.000000e+00 0.000000e+00
# O2 0.000000e+00 0.000000e+00
# OH 0.000000e+00 0.000000e+00
# H2O 0.000000e+00 0.000000e+00
# HO2 0.000000e+00 0.000000e+00
# H2O2 0.000000e+00 0.000000e+00
# C 0.000000e+00 0.000000e+00
# CH 0.000000e+00 0.000000e+00
# CH2 0.000000e+00 0.000000e+00
# CH2(S) 0.000000e+00 0.000000e+00
# CH3 0.000000e+00 0.000000e+00
# CH4 0.000000e+00 0.000000e+00
# CO 0.000000e+00 0.000000e+00
# CO2 0.000000e+00 0.000000e+00
# HCO 0.000000e+00 0.000000e+00
# CH2O 0.000000e+00 0.000000e+00
# CH2OH 0.000000e+00 0.000000e+00
# CH3O 0.000000e+00 0.000000e+00
# CH3OH 0.000000e+00 0.000000e+00
# C2H 0.000000e+00 0.000000e+00
# C2H2 0.000000e+00 0.000000e+00
# C2H3 0.000000e+00 0.000000e+00
# C2H4 0.000000e+00 0.000000e+00
# C2H5 0.000000e+00 0.000000e+00
# C2H6 0.000000e+00 0.000000e+00
# HCCO 0.000000e+00 0.000000e+00
# CH2CO 0.000000e+00 0.000000e+00
# HCCOH 0.000000e+00 0.000000e+00
# N 0.000000e+00 0.000000e+00
# NH 0.000000e+00 0.000000e+00
# NH2 0.000000e+00 0.000000e+00
# NH3 0.000000e+00 0.000000e+00
# NNH 0.000000e+00 0.000000e+00
# NO 0.000000e+00 0.000000e+00
# NO2 0.000000e+00 0.000000e+00
# N2O 0.000000e+00 0.000000e+00
# HNO 0.000000e+00 0.000000e+00
# CN 0.000000e+00 0.000000e+00
# HCN 0.000000e+00 0.000000e+00
# H2CN 0.000000e+00 0.000000e+00
# HCNN 0.000000e+00 0.000000e+00
# HCNO 0.000000e+00 0.000000e+00
# HOCN 0.000000e+00 0.000000e+00
# HNCO 0.000000e+00 0.000000e+00
# NCO 0.000000e+00 0.000000e+00
# N2 0.000000e+00 0.000000e+00
# AR 0.000000e+00 0.000000e+00
# C3H7 0.000000e+00 0.000000e+00
# C3H8 0.000000e+00 0.000000e+00
# CH2CHO 0.000000e+00 0.000000e+00
# CH3CHO 0.000000e+00 0.000000e+00
#
# What you have just done is to create an object ("gas1") that
# implements GRI-Mech 3.0, the 53-species, 325-reaction natural gas
# combustion mechanism developed by Gregory P. Smith, David M. Golden,
# Michael Frenklach, Nigel W. Moriarty, Boris Eiteneer, Mikhail
# Goldenberg, C. Thomas Bowman, Ronald K. Hanson, Soonho Song, William
# C. Gardiner, Jr., Vitali V. Lissianski, and Zhiwei Qin. See
# http://www.me.berkeley.edu/gri_mech/ for more information.
#
# The object created by GI30() has properties you would expect for a gas
# mixture - it has a temperature, a pressure, species mole and mass
# fractions, etc. As we'll soon see, it has many more properties.
#
# The summary of the state of 'gas1' printed above shows that new
# objects created by function GRI30() start out with a temperature of
# 300 K, a pressure of 1 atm, and have a composition that consists of
# only one species, in this case hydrogen. There is nothing special
# about H2 - it just happens to be the first species listed in the
# input file defining GRI-Mech 3.0 that the 'GRI30' function reads. In
# general, whichever species is listed first will initially have a
# mole fraction of 1.0, and all of the others will be zero.
# Setting the state
# -----------------
# The state of the object can easily be changed. For example,
gas1.setTemperature(1200)
# sets the temperature to 1200 K. (Cantera always uses SI units.)
# After this statement,
print gas1
# results in:
#
# temperature 1200 K
# pressure 405300 Pa
# density 0.081896 kg/m^3
# mean mol. weight 2.01594 amu
#
# X Y
# ------------- ------------
# H2 1.000000e+000 1.000000e+000
# (other species not shown)
#
# Notice that the temperature has been changed as requested, but the
# pressure has changed too. The density and composition have
# not.
#
# When setting properties individually, some convention needs to be
# adopted to specify which other properties are held constant. This is
# because thermodynamics requires that *two* properties (not one) in
# addition to composition information be specified to fix the
# intensive state of a substance (or mixture).
#
# Cantera adopts the following convention: only one of the set
# (temperature, density, mass fractions) is altered by setting any
# single property. This means that:
#
# a) Setting the temperature is done holding density and
# composition fixed. (The pressure changes.)
# b) Setting the pressure is done holding temperature and
# composition fixed. (The density changes.)
#
# c) Setting the composition is done holding temperature
# and density fixed. (The pressure changes).
#
# Instead of using a method like 'setTemperature' to set one property,
# you can use a single method 'set' to set any property or combination
# of properties:
gas1.set(Temperature = 900.0, Pressure = 1.e5)
# This statement sets both temperature and pressure at the same
# time. Any number of property/value pairs can be specified in a
# call to 'set'. For example, the following sets the mole fractions
# too:
gas1.set(Temperature = 900.0, Pressure = 1.e5,
MoleFractions = 'CH4:1,O2:2,N2:7.52')
# The 'set' function also accepts abbreviated property names:
gas1.set(T = 900.0, P = 1.0e5, X = 'CH4:1,O2:2,N2:7.52')
# Either version results in:
print gas1
# temperature 900 K
# pressure 100000 Pa
# density 0.369279 kg/m^3
# mean mol. weight 27.6332 amu
# 1 kg 1 kmol
# ----------- ------------
# enthalpy 455660 1.259e+07 J
# internal energy 184862 5.108e+06 J
# entropy 8529.31 2.357e+05 J/K
# Gibbs function -7.22072e+06 -1.995e+08 J
# heat capacity c_p 1304.4 3.604e+04 J/K
# heat capacity c_v 1003.52 2.773e+04 J/K
# X Y
# ------------- ------------
# H2 0.000000e+00 0.000000e+00
# H 0.000000e+00 0.000000e+00
# O 0.000000e+00 0.000000e+00
# O2 1.901141e-01 2.201487e-01
# OH 0.000000e+00 0.000000e+00
# H2O 0.000000e+00 0.000000e+00
# HO2 0.000000e+00 0.000000e+00
# H2O2 0.000000e+00 0.000000e+00
# C 0.000000e+00 0.000000e+00
# CH 0.000000e+00 0.000000e+00
# CH2 0.000000e+00 0.000000e+00
# CH2(S) 0.000000e+00 0.000000e+00
# CH3 0.000000e+00 0.000000e+00
# CH4 9.505703e-02 5.518632e-02
# CO 0.000000e+00 0.000000e+00
# CO2 0.000000e+00 0.000000e+00
# HCO 0.000000e+00 0.000000e+00
# CH2O 0.000000e+00 0.000000e+00
# CH2OH 0.000000e+00 0.000000e+00
# CH3O 0.000000e+00 0.000000e+00
# CH3OH 0.000000e+00 0.000000e+00
# C2H 0.000000e+00 0.000000e+00
# C2H2 0.000000e+00 0.000000e+00
# C2H3 0.000000e+00 0.000000e+00
# C2H4 0.000000e+00 0.000000e+00
# C2H5 0.000000e+00 0.000000e+00
# C2H6 0.000000e+00 0.000000e+00
# HCCO 0.000000e+00 0.000000e+00
# CH2CO 0.000000e+00 0.000000e+00
# HCCOH 0.000000e+00 0.000000e+00
# N 0.000000e+00 0.000000e+00
# NH 0.000000e+00 0.000000e+00
# NH2 0.000000e+00 0.000000e+00
# NH3 0.000000e+00 0.000000e+00
# NNH 0.000000e+00 0.000000e+00
# NO 0.000000e+00 0.000000e+00
# NO2 0.000000e+00 0.000000e+00
# N2O 0.000000e+00 0.000000e+00
# HNO 0.000000e+00 0.000000e+00
# CN 0.000000e+00 0.000000e+00
# HCN 0.000000e+00 0.000000e+00
# H2CN 0.000000e+00 0.000000e+00
# HCNN 0.000000e+00 0.000000e+00
# HCNO 0.000000e+00 0.000000e+00
# HOCN 0.000000e+00 0.000000e+00
# HNCO 0.000000e+00 0.000000e+00
# NCO 0.000000e+00 0.000000e+00
# N2 7.148289e-01 7.246650e-01
# AR 0.000000e+00 0.000000e+00
# C3H7 0.000000e+00 0.000000e+00
# C3H8 0.000000e+00 0.000000e+00
# CH2CHO 0.000000e+00 0.000000e+00
# CH3CHO 0.000000e+00 0.000000e+00
# Other properties may also be set using 'set', including some that
# can only be set in combination with others. The following property
# pairs may be set: (Enthalpy, Pressure), (IntEnergy, Volume),
# (Entropy, Volume), (Entropy, Pressure). In each case, the values of
# the extensive properties must be entered *per unit mass*.
# Setting the enthalpy and pressure:
gas1.set(Enthalpy = 2*gas1.enthalpy_mass(), Pressure = 2*OneAtm)
# This sets gas1 to a state with P = 2 atm, and a specific enthalpy
# twice its previous value.
# Note that the abbreviations T, P, H, U, S, V can also be used with
# the 'set' method.
# The composition above was specified using a string. The format is a
# comma-separated list of <species name>:<relative mole numbers>
# pairs. The mole numbers will be normalized to produce the mole
# fractions, and therefore they are 'relative' mole numbers. Mass
# fractions can be set in this way too by changing 'X' to 'Y' in the
# above statement.
# The composition can also be set using an array, which must have the
# same size as the number of species. For example, to set all 53 mole
# fractions to the same value, do this:
x = ones(53,'d'); # NumPy array of 53 ones
gas1.set(X = x)
print gas1
# To set the mass fractions to equal values:
gas1.set(Y = x)
print gas1
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