ASYMPTOTIC AND VARIATIONAL DERIVATIONS OF THE SIMPLIFIED P(N) EQUATIONS

被引：69

作者：

POMRANING, GC

机构：

[1] School of Engineering, Applied Science University of California, Los Angeles, Los Angeles

来源：

ANNALS OF NUCLEAR ENERGY | 1993年 / 20卷 / 09期

关键词：

Variational techniques;

D O I：

10.1016/0306-4549(93)90030-S

中图分类号：

TL [原子能技术]; O571 [原子核物理学];

学科分类号：

0827 ; 082701 ;

摘要：

It is demonstrated that the simplified P(N) equations are a leading Order asymptotic limit of the transport equation. This limit is one of locally nearly planar transport involving scattering which is highly peaked in the forward direction. This asymptotic equivalence is valid in full generality, in that it allows time-dependent transport in a heterogeneous medium. It is also shown that the simplified P(N) equations can be derived variationally, making use of certain trial functions in a variational characterization of the even-parity transport equation. In this case, however, there appears to be an inherent restriction to time-independent transport in a homogeneous medium.

引用

页码：623 / 637

页数：15