摘要
本文论述了变分原理的自然条件不参加变分;证明了粘性流体流动的功率消耗Ⅱ_(iv)、Ⅱ_(iv)、Ⅱ_(pc)皆只是驻值原理而不是极值原理;还提出了新的高阶变分定义,它有运算简便等优点。
This treatise argues the national conditions of variational principles not participating in the process of variation, and proves all the power lossed of viscous fluid flows Ⅱiv[1],Ⅱiv(λ)[1],Ⅱpc[1] are only stationary principles but are not maximum principles. This treatise also presents a new definition of high-order variations, which are with some advantages, e. g., their operations are simpler and more convenient.
出处
《北京大学学报（自然科学版）》
CAS
CSCD
北大核心
1990年第3期291-297,共7页
Acta Scientiarum Naturalium Universitatis Pekinensis
关键词
粘性流动
功率消耗
变分
自然条件
Hydrodynamics of viscous fluids
Generalized variational principle
Calculus of Variations
