Hnm. Gheorghiu et F. Rahnema, GENERALIZED RAYLEIGH QUOTIENTS FOR EIGENVALUE ESTIMATES OF NEUTRON BALANCE-EQUATIONS, Nuclear science and engineering, 125(3), 1997, pp. 314-323
Generalized Rayleigh quotients are developed to provide estimates of t
he eigenvalues of the continuous-energy transport equation and its dif
fusion approximation. The new variational principles extend the applic
ability of the quotient to perturbations of the boundary as well as th
e boundary condition of the system. As a result, all three (operator,
boundary condition, and external boundary) perturbation types can now
be treated simultaneously, and the standard Rayleigh quotient appears
as a special case of the variational principles given in this paper. T
he correctness of the principles are verified by reproducing the first
-order perturbation results and considering some numerical examples fo
r the case of boundary perturbation.