天文学报
天文學報
천문학보
ACTA ASTRONOMICA SINICA
2001年
1期
81-87
,共7页
黄乘利%廖新浩%朱耀仲%金文敬
黃乘利%廖新浩%硃耀仲%金文敬
황승리%료신호%주요중%금문경
章动%地球自转%边界条件
章動%地毬自轉%邊界條件
장동%지구자전%변계조건
在研究地球章动或潮汐理论时,常常需要对均匀自转、微椭、弹性、自引力的地球的运动方程组积分,并通过选取一组恰当的边界条件来定解.在一阶扁率近似下,先将椭球形参考边界上一个有关形变的连续量转化到等效球面上,然后作广义面球谐函数展开进行标量化,并分解为球形与环形部分,截断后可导出3个标量常微分形式的边界条件.
在研究地毬章動或潮汐理論時,常常需要對均勻自轉、微橢、彈性、自引力的地毬的運動方程組積分,併通過選取一組恰噹的邊界條件來定解.在一階扁率近似下,先將橢毬形參攷邊界上一箇有關形變的連續量轉化到等效毬麵上,然後作廣義麵毬諧函數展開進行標量化,併分解為毬形與環形部分,截斷後可導齣3箇標量常微分形式的邊界條件.
재연구지구장동혹조석이론시,상상수요대균균자전、미타、탄성、자인력적지구적운동방정조적분,병통과선취일조흡당적변계조건래정해.재일계편솔근사하,선장타구형삼고변계상일개유관형변적련속량전화도등효구면상,연후작엄의면구해함수전개진행표양화,병분해위구형여배형부분,절단후가도출3개표량상미분형식적변계조건.
The scalar equations of infinitesimal elastic-gravitational motion for a rotational, slightly elliptical Earth are always used to study the Earth's nutation and tides theoretically,while the determination of the integration of the equations depends, in a certain extent, upon the choice of a set of boundary conditions. In this paper, a continuous quantity related to the displacement is transformed from the elliptical reference boundary to the corresponding effective spherical domain, and converted from vector (or tensor) form to scalar form by generalized surface spherical harmonics expansion. All the related components, including the displacement field (or the stress tensor field), are then decomposed into the poloidal and toroidal fields. After being truncated, the boundary conditions are derived, at last, in scalar ordinary differential format. The procedure of the derivation is in the order of the ellipticity and in full details.