排序方式: 共有21条查询结果,搜索用时 78 毫秒
1.
2.
A cascade profile design method was proposed using the aerodynamic load and blade thickness distribution as the design constraints, which were correspondent to the demands from the aerodynamic characteristics and the blade strength. These constraints,together with all the other boundary conditions , were involved in the stationary conditions ofa variational principle , in which the angle-function was employed as the unknown function.The angle-function ( i. e. , the circumferential angular coordinate) was defined in the image plane composed of the stream function coordinate ( circumferential direction ) and streamline coordinate. The solution domain, i.e., the blade-to-blade passage, was transformed into a square in the image plane, while the blade contour was projected to a straight line ; thus, the difficulty of the unknown blade geometry was avoided. The finite element method was employed to establish the calculation code. Applications show that this method can satisfy the design requests on the blade 相似文献
3.
4.
基于气动载荷与叶片厚度分布的叶栅气动设计方法 总被引:1,自引:0,他引:1
建立一种以载荷与叶片厚度分布为约束的叶栅气动设计计算方法,约束条件体现了气动特性与强度两方面的要求,这些约束及其它所有边界条件,都包含在相应的变分原理的驻值条件中。变分原理以周角函数为泛函的未知函数,周角函数定义在由流线坐标与流函数坐标(周向)构成的映象面上。在映象面上,求解域——叶栅通道——化作一个矩形,叶片型线映射为一条水平直线,从而避免了叶片外形未知的困难。利用有限元方法建立了计算程序,算例显示这种方法能有效地满足对叶片型线的设计要求,而且迭代计算具有良好的收敛性。 相似文献
5.
6.
7.
8.
9.
基于Hamilton体系研究了Eringen的非局部线弹性本构关系.Eringen的非局部线弹性理论存在积分型和微分型两类本构关系.由于方程的形式简单,目前多采用微分型本构;而积分型本构方程是典型的积分-微分方程,数值求解较为困难.在分析结构力学中提出的界带分析方法,成功求解了时间滞后问题的积分-微分方程.根据分析动力学与分析结构力学的模拟关系,将界带分析方法引入到非局部理论的积分型本构方程,可以实现积分-微分方程的数值求解.通过杆件的振动分析算例验证了该套理论算法的准确性和可行性,也指出了辛体系算法在非局部力学问题中的潜力. 相似文献
10.
基于Eringen提出的Nonlocal线弹性理论的微分形式本构关系,导出了相应的能量密度表达式,进而得到二维Nonlocal线弹性理论的变分原理.利用变分原理导出了对偶平衡方程和相应的边界条件.进而给出了非局部动力问题的Lagrange函数,并引入对偶变量和Hamilton函数,得到了对偶体系下的变分方程.在Hamilton体系下,通过变分得到了二维Nonlocal线弹性理论的对偶平衡方程和相应的边界条件. 相似文献