Kinetic Theory of Molecular Gases I: Models of the Linear Waldmann–Snider Collision Operator

Using a method closely akin to the Gross–Jackson–Sirovich procedure, we present a modeling theory of the linear Waldmann–Snider collision operator. The resulting model kinetic equations are applicable to all regions of wavelength and frequency consistent with the original equation itself. The theory is made parameter free by relating the matrix elements of the collision operator to measured transport properties. It is sophisticated enough to afford a study of both scalar and tensorial phenomena and can be applied to the analysis of a variety of initial and boundary value problems.