Accession Number : AD0680390

Title :   RADIATIVE ENERGY TRANSFER FROM A SMALL SPHERE.

Descriptive Note : Technical rept. Apr-Jun 68,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Emanuel,George

Report Date : OCT 1968

Pagination or Media Count : 29

Abstract : The emissive power and radiant heat flux are determined for a single sphere in a quiescent nonconducting grey gas when the radius of the sphere is small compared to a photon mean free path. It is shown by the method of matched asymptotic expansions that the leading term of the inner solution, which is valid near the sphere, corresponds to the solution with an optically thin gas. The leading term of the outer solution is for a point source in an infinite medium. Neutron transport theory provides the solution to this problem. A uniformly valid first approximation is found for the emissive power, while the first two approximations are determined for the heat flux. A comparison is made with other approximate and numerical solutions. (Author)

Descriptors :   (*THERMAL RADIATION, GASES), SPHERES, KINETIC THEORY, APPROXIMATION(MATHEMATICS), NEUTRON TRANSPORT THEORY, EMISSIVITY, HEAT FLUX, CORRELATION TECHNIQUES

Subject Categories : Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE