基于PREM的地球引力势二阶系数的潮汐摄动

TIDAL PERTURBATION OF GEOPOTENTIAL COEFFICIENTS OF SECOND ORDER BASED ON THE PREM RHEOLOGICAL PARAMETERS

地球引力势系数变化的研究涉及到人造卫星运动跟踪精度的提高和动力学模型的改进．本文利用目前较完善的地球模型ＰＲＥＭ所给出的流变学参数，通过求解弹性地幔运动方程，得到在日月引潮力作用下的形变位移矢量，进而计算了地球引力势二阶系数的潮汐周期摄动．指出在高精度的人造卫星跟踪数据的分析研究中，不能忽略因潮汐形变引起的δＪ２和δＪ２２的影响．

The analysis of the variation of the geopotential coefficients involves an increase of the tracking accuracy of satellite motion and the improvement of the dynamic models. In this paper, the rheological parameters given by Earth model PREM are adopted and the equations of motion of the elastic mantle are solved, thus obtaining the deformable displacement vectors caused by lunisolar tidal generation force. Then the analytical expressions are given for the periodic variations of geopotential coefficients of second order due to the deformation and the tidal periodic perturbation is calculated. The results show the periodic variations of the geopotential coefficients of second order should not be ignored in studies of satellite tracking data with a high intrinsic accuracy. The procedure can be applied to predicting the tidal periodic variation of the geopotential coefficients.