微分方程

Axisymmetric elasticity problem of cubic quasicrystal is reduced to a solution of a partial differential equation with higher-order by introducing displacement function.

本文通过引入位移函数使得立方准晶的轴对称弹性问题化为求解一高阶偏微分方程。

The condensability of liquid,the Westphal's effect and the continuous flow condition are not only comprehensively considered,but also the dynamic property of the ball valve being established.

结合现场试验,根据直线电机采油泵运动特性,综合虑了液体的可压缩性、魏氏效应、液体连续流动条件和球阀的动力特性,建立了直线电机采油泵球阀运动规律的精确运动微分方程组。