Chemical equilibrium at constant internal energy and volume#
1% -------------------------------------------------------------------------
2% EXAMPLE: EV
3%
4% Compute equilibrium composition at adiabatic temperature and defined
5% specific volume v = 1 m3/kg for lean to rich CH4-air mixtures at temperature
6% T = 300 K, and a set of equivalence ratios (phi) contained in (0.5, 5) [-]
7%
8% See wiki or setListspecies method from ChemicalSystem class for predefined
9% sets of species
10%
11% @author: Alberto Cuadra Lara
12%
13% Last update October 06 2025
14% -------------------------------------------------------------------------
15
16% Import packages
17import combustiontoolbox.databases.NasaDatabase
18import combustiontoolbox.core.*
19import combustiontoolbox.equilibrium.*
20
21% Get Nasa database
22DB = NasaDatabase();
23
24% Define chemical system
25system = ChemicalSystem(DB);
26
27% Initialize mixture
28mix = Mixture(system);
29
30% Define chemical state
31set(mix, {'CH4'}, 'fuel', 1);
32set(mix, {'N2', 'O2', 'Ar', 'CO2'}, 'oxidizer', [78.084, 20.9476, 0.9365, 0.0319] / 20.9476);
33
34% Define properties
35mixArray = setProperties(mix, 'temperature', 300, 'volume', 1, 'equivalenceRatio', 0.5:0.01:5);
36
37% Initialize solver
38solver = EquilibriumSolver('problemType', 'EV');
39
40% Solve problem
41solver.solveArray(mixArray);
42
43% Generate report
44report(solver, mixArray);