含哈密顿算子的并联式内积张量泛函变分问题  

Variational Problems of the Functional of Parallel-Type Inner Product Tensor with Hamiltonian Operators

作　　者：老大中[1] 张彦迪[2] 杨策[3] LAO Da-zhong;ZHANG Yan-di;YANG Ce(School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China;Yinchuan University of Energy, Yinchuan, Ningxia 750105, China;School of Mechanical Engineering, Beijing Institute of Technology,Beijing 100081, China)

机构地区：[1]北京理工大学宇航学院,北京100081 [2]银川能源学院,宁夏银川750105 [3]北京理工大学车辆工程学院,北京100081

出　　处：《北京理工大学学报》2019年第4期419-426,共8页Transactions of Beijing Institute of Technology

基　　金：国家自然科学基金资助项目(51576015)

摘　　要：讨论变分法中含哈密顿算子即梯度、散度和旋度的并联式张量的泛函变分问题.根据n阶张量并联式内积和串联式内积运算规则,给出张量泛函变分问题的基本引理.提出并证明含哈密顿算子的张量泛函变分问题的定理;通过直接对张量的梯度、散度和旋度进行变分,得到欧拉方程和相应的自然边界条件.通过若干算例验证了欧拉方程的正确性.扩展伴随算子的内涵,提出右伴随算子的概念,讨论伴随算子或自伴算子与梯度、散度和旋度算子的关系,指出所讨论的泛函变分问题实质上是符合伴随算子或自伴算子定义的运算.The variational problems of the functional depending on parallel-type inner product tensor in the calculus of variations were discussed, the tensor in the functional can include Hamiltonian operator namely the gradient, divergence and curl operator. According to the parallel-type and serial-type inner product operation rules of the n -th order tensor, the fundamental lemma of the variational operations of the functional depending on the tensor was given. The theorem of the variational problem of the functional depending on the tensor with Hamiltonian operators was proposed and proved;Through making directly variation to the tensors with Hamiltonian operators, the Euler equation and the corresponding natural boundary conditions were obtained. The correctness of the Euler equation was verified with some functional examples. The connotation of the dajoint operator was extended, the conception of the right adjoint operator was proposed, the relationships between the adjoint operator or self-adjoint operator and the gradient, divergence and curl operator were discussed, it is pointed out that the variational problem of the functional discussed is essentially operation conforming to the definition of adjoint operator operation or self-adjoint operator.

关 键 词：变分法 哈密顿算子 张量 泛函 变分问题 欧拉方程 伴随算子 自伴算子 

分 类 号：O176[理学—数学]