查询词典 unsteady

Taking HPAM solutions as an example, the unsteady flow of power-law fluid in eccentric annuli with the inner cylinder reciprocating axially is calculated; the distribution of velocity, flow rate and stability parameter is obtained; taking HEC solutions as another example, the flow of second order fluid in eccentric annuli with the inner cylinder moving axially is calculated too; the distribution of velocity and stress is obtained; the effect of eccentricity and axial movement on stress distribution on the outwall of the inner cylinder is analysed.

在理论上，分别用二阶流体和幂律流体模型描述聚合物驱油井产出液的非Newton流变性；分别建立了双极坐标系下二阶流体和幂律流体在内管做轴向往复运动的偏心环空中非定常流的控制方程及边界条件和初始条件方程；建立了幂律流体在内管做轴向往复运动的偏心环空中流动的稳定性参数和流体在内管壁上的压力分布计算公式；建立了二阶流体在内管做轴向运动的偏心环空中流动的流体在内管壁上的压力分布计算公式。

According to the hydraulic property of overflow weirs under steady flow, the flow patterns of overflow weirs were classified into free overfall and submerged overfall, and numerical models for unsteady flow were established to simulate the two flow patterns respectively.

摘要为了对保水堰的交替水流进行数值模拟，依据保水堰恒定流情况下的工作特性，将保水堰的水流形态分成堰流和满流两种状态，分别建立保水堰不同流态下的非恒定流数学模型。

A fourth-order compact finite difference alternating-direction-implicit algorithm is proposed for solving the unsteady-state Navier-Stokes equations of fluid flow and heat transfer using the streamfunction-vorticity formulation. Point-successive overtaxation iteration is used to achieve the steady solutions.

本文构造了求解二维非定常涡量流函数形式Navier-Stokes方程组的一种四阶紧致交错方向隐式差分算法，对包括能量方程在内的离散化方程组采用逐次超松驰迭代法求得稳定解，求解了二维非定常粘性不可压缩流体的流动与传热问题。

In the second part the pectoral fin motion model of 2 degrees and 3 degrees of freedom is constructed. Also we use Unsteady Vortex Lattice Method to analyze the hydrodynamic performance of the pectoral fin motion.

第二部分建立刚性胸鳍二自由度、三自由度的运动模型，并用非定常涡格法计算和分析了胸鳍的水动力性能。

Comparison between the velocity distributions at the different flow rate conditions showed that increasing the flow rate was help to improving the velocity distribution. The periodic mean field on r-6 plane at different axis positions showed that the flow within the vaned diffuser, especially within the inlet region, was periodic unsteady when impeller located at the different circumferential position, just as the flow within the vaneless diffuser.

有叶扩压器内平均流场的分析表明，在定常流动的假设下，不同流量工况下有叶扩压器的内部流动也呈现为沿轴线向后盘方向推移流动状况逐渐恶劣的分布规律，表明二元叶片构成的平行直壁有叶扩压器对轴向不均匀流动的掺混作用仍然不大。

The operation of periodic flow reversal is a new kind of unsteady-state reaction techniques.

流向变换周期操作是一种非稳态催化反应新技术，其反应器模型一般为非线性反应－对流－扩散方程的新型定解问题。

The results of computations show that the structure of unsteady flow is complex during both the acceleration phase and the constant velocity phase.

计算结果表明启动过程绕大攻角翼型的加速流动结构复杂，该瞬态过程的流动分离现象也明显区别于稳态过程自生和自维持的分离流动，并且启动加速度大小对流动的分离、漩涡结构和强度等都有直接影响。

The discharge calculation coefficient k,x can be used to the discharge calculation under the condition of fixed numerical value,solves some special demands in water power planning and design and similar calculation of unsteady flow in the pondage water power station.

马斯京根法流量演进系数K，x，在数值不变的条件下应用于河段短时段的流量演算，解决了水利水电工程规划设计中的一些特殊要求和水电站日调节不稳定流演进的近似计算问题。

Working on this project will open a new road to explore the potential of unsteady flow.

对此方向的深入研究，对于进一步挖掘叶轮机非定常流动的潜力开辟一条新的道路。

Firstly, based on the method of pressure-velocity coupling introduced by SIMPLE algorithm and a revised method of solving the unsteady equation of stream function and vorticity on uniform grid, a special algorithm called primitive-variable-time-dependent approach is formed in the present study. In this algorithm the Navier-Stokes equation in primitive variable form is solved by using the time-dependent approach on non-uniform staggered grid system. The second-order accuracy finite difference is used for the first and second partial derivatives of all variables of the convective terms and diffusion terms.

首先，本文在SIMPLE算法系列处理速度与压力耦合问题的思路和均匀网格下改进的关于流函数涡量方程的数值求解方法的基础上，将非定常原始变量Navier-Stokes方程的求解推广至非等距交错网格剖分，形成了具有本文特色的原始变量时间推进方法，其中对流项和扩散项中各变量的各阶导数均采用二阶精度公式，包括温度在内的离散方程组采用ADI迭代方法求解。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。