三轴刚体地球自转的两种解法研究

The reasearch on two solutions of the triaxial rigid earth rotation

地球的非对称性对地球自转是有一定影响的,其理论研究是有意义的.文献[20]认为三轴刚体地球除了具有欧拉自由摆动外,还存在第二自由摆动,长期极移是自由摆动的结果,以及地球自转存在自由加速等.本文研究了三轴刚体地球自转的动力学方程,基于传统的求解方法,给出了三轴刚体地球的自由摆动解.同时列出了文献[20]对三轴刚体地球自转的求解方法,探讨了其在推导过程的若干不足,最后指出三轴刚体地球自转只存在欧拉摆动,不存在第二自由摆动.

The non symmetry of the earth has a some influence on it＇s rotation, the theoretical researches for the triaxial Earth model should have definite meanings. The literature [20] considered that there is secondary free wobble for the triaxial rigid earth, besides Eulerian wobble. The secular polar motion is a result of the free wobble of the triaxial earth, as well as, exists free acceleration or deceleration in the earth rotation. This paper investigates the dynamical equation for the triaxial rigid earth rotation based on the traditional solved method, and gives a solution of free wobble. At the same time, the solved methods presented by the literature [20] are also listed, and some shortages in it＇s deductive process are discussed. Finally, this paper indicates that there is only Eulerian wobble, and no second free wobble for the triexial elastic Earth model.