从力学的变分原理出发,得到了受非保守约束力的Hamilton系统的动力学方程的离散形式和能量演化方程,即保结构数值算法格式. 给出了非保守Hamilton系统的离散Lie对称性判定方程;基于离散Noether定理推导出系统Noether守恒量的离散形式. 最后举例说明本文结论的合理性.
The difference equations and the energy equation of the nonconservative Hamiltonian systems are proposed by introducing the discrete difference variational principle.The structure-preserving algorithms are proposed for these equations.The discrete determining equations of the Lie symmetries are obtained. The conserved quantities of the systems are given through the discrete Noether theorem. An example is given to illustrate the results.
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