Warning

This documentation is for an old version of Cantera. You can find docs for newer versions here.

```
% Tutorial 6: Transport properties
%
% Topics:
% - mixture-averaged and multicomponent models
% - viscosity
% - thermal conductivity
% - binary diffusion coefficients
% - mixture-averaged diffusion coefficients
% - multicomponent diffusion coefficients
% - thermal diffusion coefficients
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Methods are provided to compute transport properties. By
% default, calculation of transport properties is not enabled. If
% transport properties are required, the transport model must be
% specified when the gas mixture object is constructed.
% Currently, two models are implemented. Both are based on kinetic
% theory expressions, and follow the approach described in Dixon-Lewis
% (1968) and Kee, Coltrin, and Glarborg (2003). The first is a full
% multicomponent formulation, and the second is a simplification that
% uses expressions derived for mixtures with a small number of species
% (1 to 3), using approximate mixture rules to average over
% composition.
% To use the multicomponent model with GRI-Mech 3.0, call function
% GRI30 as follows:
g1 = GRI30('Multi')
% To use the mixture-averaged model:
g2 = GRI30('Mix')
% Both models use a mixture-averaged formulation for the viscosity.
visc = [viscosity(g1), viscosity(g2)]
% The thermal conductivity differs, however.
lambda = [thermalConductivity(g1), thermalConductivity(g2)]
% Binary diffusion coefficients
bdiff1 = binDiffCoeffs(g1)
bdiff2 = binDiffCoeffs(g2)
% Mixture-averaged diffusion coefficients. For convenience, the
% multicomponent model implements mixture-averaged diffusion
% coefficients too.
dmix2 = mixDiffCoeffs(g1)
dmix1 = mixDiffCoeffs(g2)
% Multicomponent diffusion coefficients. These are only implemented
% if the multicomponent model is used.
dmulti = multiDiffCoeffs(g1)
% Thermal diffusion coefficients. These are only implemented with the
% multicomponent model. These will be very close to zero, since
% the composition is pure H2.
dt = thermalDiffCoeffs(g1)
% Now change the composition and re-evaluate
set(g1,'X',ones(nSpecies(g1),1));
dt = thermalDiffCoeffs(g1)
% Note that there are no singularities for pure gases. This is
% because a very small positive value is added to all mole
% fractions for the purpose of computing transport properties.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
clear all
cleanup
```