A compact formulation for multi-component transport coefficients in gas mixtures

A linearly independent set of generalized cross-sections and their ratios is identified to describe all the elements of the system matrices needed to evaluate transport coefficients in dilute, field-free, gas mixtures with an arbitrary number of polyatomic species. The cross-section ratios are also defined in terms of more customary collision integrals and are related to a number of macroscopic observables. The practical advantages of the proposed formulation when performing calculations of transport coefficients for computationally demanding flow simulations are discussed.