查询词典 unsteady

By Ensemble-averaged Method, the mean field was got to show the 3D structure of flow. By Phase-locked Averaged Technique, the periodic mean field was got to reflect the periodic unsteady characteristic. The 3D structure and the periodic unsteady characteristic of the unsteady flow within the vaneless and vaned diffuser were discussed through analyzing the mean field and the periodic mean field.

离心风机扩压器内非定常流动的实验研究本文完成了离心风机两种结构条件下无叶扩压器、有叶扩压器内部的非定常流动瞬态全流场的实验测量，获得了不同运行工况下PIV的瞬态流谱，为研究扩压器内部非定常流动提供了基础实验资料。

However, the effect from impeller did not keep to the outlet of the vaneless diffuser. Through analyzing the periodic mean field, an unsteady effect region was found within the region whose biggest radius ratio was less than 1. 2 in the vaneless diffuser. The unsteady flow at three flow rate conditions had the similar unsteady characteristic.

无叶扩压器内近前盘r-6面上锁相平均流场的分析表明，当叶轮处于不同周向位置时，无叶扩压器内的流动表现出非定常流动特性，尤其是在人口区域非定常流动特性更为明显。

Not only is the method applied in this paper better to solve the iteration between unsteady convection and conduction and the boundary condition problem, but also is a developmental application on forward and backward difference of windward scheme under unsteady condition.

不仅较好地解决了对流换热和导热的迭代求解和边界条件的处理问题，还将迎风格式的向前和向后差分发展性地应用于非稳态求解过程。

Based on Bernoulli equation of unsteady flow, a random walk model is presented firstly for numerical simulation of unsteady flow in river networks.

首次从非恒定流能量方程出发，建立随机游动模型，用蒙特卡罗方法数值模拟大型河网非恒定水流运动。

The response of a delta wing in unsteady free stream was investigated in the unsteady wind tunnel of NUAA.

在南航非定常风洞中，详细研究了非定常自由流对三角翼气动特性的影响。

Therefore, a similarity solution of velocity distribution exists in such unsteady Navier-Stokes equations; In chapter 3, the unsteady flow of a viscoelastic fluid with the fractional derivative Maxwell model in rectangular tube is studied.

因而，给出了不定常Navier-Stokes方程速度分布的一相似性解；第三章研究了具有分数阶Maxwell模型的粘弹性流体在矩形管内的不定常流动。

In the first part, first, the operational principle of Varivec Propeller is explained. Secondly, the mathematical model for predicting longitudinal and transverse movement hydrodynamic characteristics of Varivec Propeller under steady or unsteady condition are present, based on the general propeller lifting-surface theory, potential flow theory and Green theorem. Thirdly, theoretical calculation methods for predicting hydrodynamic characteristics when the influence of paraboloidal boss on the performance of Varivec Propeller is or isn't considered are present, based on The finite basic solution method, the unsteady vortex lattice method and Hess-Smith method Different rake angle is adopted according to different desire in practical application.

在理论计算部分，本文首先给出了全方向推进器的工作原理，然后基于常规螺旋桨升力面理论、势流理论和格林定理建立了定常和非定常状态下全方向推进器纵向、横向运动的水动力性能计算的数学模型，并利用有限基本解法、非定常涡格法和Hess-smith方法分别对考虑和不考虑桨毂影响时的全方向推进器纵向、横向运动水动力性能进行了数值预报。

An unsteady aerodynamic model based on Fourier analysis is developed in the frequency domain with the theory of system identification and the experimental data of large amplitude harmonic oscillation. This unsteady aerodynamic mathematical model is used to extract dynamic derivatives, and the meaning of a time-lag loop is analyzed.

应用系统辨识理论，利用纵向大振幅非定常气动力实验数据，在频率域内建立了基于Fourier变换法的非定常气动力数学模型，并发展了一种获取常规动导数的仿真实验方法，分析了迟滞环的物理意义。

In this paper, a high order accuracy difference method is presented for solving unsteady convection diffusion equation by using Implicit Perturbation Finite Difference scheme. Firstly, we use the steady convection diffusion equation, the constant coefficients of this equation are expanded to power series of grid-spacings, then the high-order Perturbation Finite Difference scheme is obtained by determining the coefficients of the power series. Put this scheme on unsteady convection diffusion equations and modified it, the IPFD scheme is constructed.

本文利用摄动差分思想，对定常对流扩散方程中的空间微商系数进行摄动展开，展开幂级数系数通过消去摄动格式修正微分方程的截断误差项求出，由此获得方程的隐式摄动差分格式，将此方法应用于非定常对流扩散方程，并加以修正，得到该方程的修正隐式摄动差分格式。

There are several processing mode of the unsteady Kuta condition, a appropriate choice will improve the convergence velocity of iterative, this paper has choosed the dipole intensity near the training edge is polynomial distribution to satisfy the unsteady Kuta condition by compare experiment.

非定常库塔条件的处理有多种，合适的处理方式有助于提高迭代收敛的速度，通过对不同处理方式的尝试比较，选取尾缘附近偶极子强度为多项式分布来满足非定常库塔条件。

The network space is the typical form of abstract space when it comes to the digital stage.

网络空间是抽象空间数字化阶段的典型形式。

The Notarial System,as the system of judicial certification in our country,is both the constructor and the defender of social credit system,It has its special value and function in the social honesty.

公证制度作为我国司法证明制度，既是社会信用体系的建设者，同时也是社会信用的捍卫者，在诚信中有其特殊的价值和功能。