2528df0f75
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.
106 lines
2.6 KiB
Matlab
Executable file
106 lines
2.6 KiB
Matlab
Executable file
function ignite2(g)
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% IGNITE2 Zero-dimensional kinetics: adiabatic, constant volume.
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%
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% This example illustrates how to use function 'reactor_ode' for
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% zero-dimensional kinetics simulations with arbitrary heat flux
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% and volume vs. time. Here a constant-volume, adiabatic simulation
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% is conducted by setting vdot and q to zero.
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%
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help ignite2
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if nargin == 1 & isa(g,'GasMix')
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gas = g;
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else
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gas = IdealGasMix('gri30.xml');
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end
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nsp = nSpecies(gas);
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% set the initial conditions
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set(gas,'T',1001.0,'P',oneatm,'X','H2:2,O2:1,N2:4');
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y0 = [intEnergy_mass(gas)
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1.0/density(gas)
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massFractions(gas)];
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time_interval = [0 0.001];
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options = odeset('RelTol',1.e-5,'AbsTol',1.e-12,'Stats','on');
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t0 = cputime;
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out = ode15s(@reactor_ode,time_interval,y0,options,gas,@vdot,@area,@heatflux);
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disp(['CPU time = ' num2str(cputime - t0)]);
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plotdata = output(out,gas);
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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% the functions below may be defined arbitrarily to set the reactor
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% boundary conditions - the rate of change of volume, the heat
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% flux, and the area.
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% Rate of change of volume. Any arbirtrary function may be implemented.
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% Input arguments:
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% t time
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% vol volume
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% gas ideal gas object
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function v = vdot(t, vol, gas)
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v = 0.0; %constant volume
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%v = 1.e11 * (pressure(gas) - 101325.0); % holds pressure very
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% close to 1 atm
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% heat flux (W/m^2).
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function q = heatflux(t, gas)
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q = 0.0; % adiabatic
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% surface area. Used only to compute heat transfer.
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function a = area(t,vol)
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a = 1.0;
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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% Since the solution variables used by the 'reactor' function are
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% not necessarily those desired for output, this function is called
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% after the integration is complete to generate the desired
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% outputs.
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function pv = output(s, gas)
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times = s.x;
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soln = s.y;
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[m n] = size(times);
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pv = zeros(nSpecies(gas) + 4, n);
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set(gas,'T',1001.0,'P',oneatm);
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for j = 1:n
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ss = soln(:,j);
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y = ss(3:end);
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mass = sum(y);
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u_mass = ss(1)/mass;
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v_mass = ss(2)/mass;
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setMassFractions(gas, y);
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setState_UV(gas, [u_mass v_mass]);
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pv(1,j) = times(j);
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pv(2,j) = temperature(gas);
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pv(3,j) = density(gas);
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pv(4,j) = pressure(gas);
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pv(5:end,j) = y;
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end
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% plot the temperature and OH mole fractions.
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figure(1);
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plot(pv(1,:),pv(2,:));
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xlabel('time');
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ylabel('Temperature');
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title(['Final T = ' num2str(pv(2,end)) ' K']);
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figure(2);
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ioh = speciesIndex(gas,'OH');
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plot(pv(1,:),pv(4+ioh,:));
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xlabel('time');
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ylabel('Mass Fraction');
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title('OH Mass Fraction');
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