论文标题
2n-stream辐射转移
2n-Stream Radiative Transfer
论文作者
论文摘要
我们使用2N流，其中n是一个整数，轴向对称辐射来求解分层介质的传递方程。这是Schuster经典2流模型的概括。众所周知，仅使用第一个2N Legendre多项式来描述辐射的角度依赖性在2N维空间中降低传递到一阶微分方程的方程。将辐射表征为2N流强度在天顶角的2N流强度，其余弦被称为2N高斯 - legendre余弦，其定义为将2N的legendre多项式等同于零。我们展示了如何使用载体和基质方法有效，准确地求解转移方程，类似于用于求解Schroedinger的量子力学方程的传递方程。为了模拟强烈的前向散射，例如地球云的可见光，我们引入了一个新的相函数。这些为从第一个2P Legendre多项式构建的相位构建的相函数提供了最大可能的正向散射P（P+1），其中P是整数。我们展示了用这种新方法计算出的辐射转移现象的说明性例子。
We use 2n streams, where n is an integer, of axially symmetric radiation to solve the equation of transfer for a layered medium. This is a generalization of Schuster's classic 2 stream model. As is well known, using only the first 2n Legendre polynomials to describe the angular dependence of radiation reduces the equation of transfer to a first order differential equation in a space of 2n dimensions. It is convenient to characterize the radiation as 2n stream intensities propagating at zenith angles having cosines called the 2n Gauss-Legendre cosines defined to be solutions of equating the Legendre polynomial of degree 2n to zero. We show how to efficiently and accurately solve the equation of transfer with vector and matrix methods analogous to those used to solve Schroedinger's equation of quantum mechanics. To model strong forward scattering, like that of visible light by Earth's clouds, we have introduced a new family of phase functions. These give the maximum possible forward scattering p(p+1) for a phase function constructed from the first 2p Legendre polynomials, where p is an integer. We show illustrative examples of radiative-transfer phenomena calculated with this new method.
