太阳大气中非线性波的数字计算

本文用多方过程方程式封闭一维带引力场的流体力学方程组,用不同的γ值计算了不同类型的扰动在HSRA太阳大气模型中向上传播和演化。说明在太阳大气中向上传播的小扰动能够发展成为激波;激波的形成高度基本上不受热力学过程的影响,而与扰动强度关系很大,愈小的扰动传播愈高;但由于太阳大气中湍流场的存在,完全有可能使这样小的扰动在未形成激波前就被破坏掉。这就证实了一些人认为的对流层机械波并不是一个对色球和日冕的有效加热机制的说法。 

NUMERICAL COMPUTATIONS OF NON-LINEAR WAVES IN SOLAR ATMOSPHERE

We computed the upward propagation and evolution of different kinds of perturbations in the solar atmosphere,using HSRA as the unperturbed model.The dynamical equation used is an one dimensional compressible flow equation under gravitational acceleration at the solar surface.Polytropic gas equations of different γ's are used to close this equation set.Our results show that an upward progagated small perturbation can evolve into shocks at certain heights which are nearly independent of the thermodynamic processes involved,but depending strongly upon the strength of the initial perturbation.But the existence and interference of the turbalent field in the solar atmosphere will not allow these perturbations to develop into shocks.This confirms the idea that the mechanical waves generated from the convection zone are not very effective in heating the chromosphere and corona.