Accession Number : AD0672195

Title :   SOLUTIONS OF BOLTZMANN EQUATION AND TRANSPORT PROCESSES.

Descriptive Note : Technical rept.,

Corporate Author : PURDUE UNIV LAFAYETTE IND PROJECT SQUID HEADQUARTERS

Personal Author(s) : Desai,Rashmi C. ; Ross,John

Report Date : JUN 1968

Pagination or Media Count : 42

Abstract : An Integral Approximation (IA) method is proposed for the solution of certain integro-differential equations of which the linearized Boltzmann equation is one example. The lowest order solution in this method consists of replacing the integral operator of the equation by a known function such that the solution has the correct initial value, correct initial slope in time and correct behavior at large times. The deviation of the integral operator from the function is treated as a perturbation in higher orders. The method is applied as an example to the calculation of the time correlation functions and thermal transport coefficients. Deviations from the exponential behavior of the correlation functions are explicitly evaluated. Another method of solution which involves a cumulant expansion (CU) is also used for the evaluation of these quantities. Both methods are then compared with the Chapman-Enskog (CE) method. The IA method provides a better physical approximation and better numerical estimates for the thermal transport coefficients than the CU or CE method. (Author)

Descriptors :   (*TRANSPORT PROPERTIES, MATHEMATICAL ANALYSIS), DIFFERENTIAL EQUATIONS, INTEGRAL EQUATIONS, IRREVERSIBLE PROCESSES, DIFFUSION, SHEAR STRESSES, VISCOSITY, THERMAL CONDUCTIVITY, CORRELATION TECHNIQUES, FUNCTIONAL ANALYSIS, APPROXIMATION(MATHEMATICS)

Subject Categories : Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE