查询词典 aerodynamic

The aerodynamic forces experiments for rigid and flexible wing are tested on the aerodynamic force measure equipment which is designed and developed by ourselves.

探讨了神经网络在驻飞飞行的姿态控制系统中的应用，最后采用MATLAB软件对控制系统进行了仿真分析。

As an important component of it,Aerodynamic property is the primary bases of ballistic curve calculation, load calculation,controlling parameter choice, the pushing force of engine choice and material choice,therefore, it is very important to researching the aerodynamic property .

气动特性作为其研究过程中的主要组成部分，它是进行弹道计算、载荷计算和控制参数选择、发动机推力选择、材料选择的原始依据。

The first half of the data is used for aerodynamic coefficients modeling, and the second half is used for verification of the resulting model based on pre-estimation of ballistic curve, the results indicate the wavelet network model of aerodynamic coefficients has generalization ability and applicability.

最后，通过建立某导弹飞行器六自由度动力学模型并进行仿真，得到样本数据，将其中一半数据用于小波网络气动力系数建模，模型参数辨识完成后，基于弹道重构原理将模型代入动力学系统进行弹道预测，将预测结果与另一部分样本数据进行比较以检验模型的推广能力，结果表明所建模型具有很好的推广能力和适用性。

This method employs the exponential pulse time series as input to excite CFD model, which can provide slick aerodynamic forces acting on the body through CFD simulation, Then discrete time aerodynamic models, defined among interesting range of frequency, can be trained based on the CFD input output relationship, those models can he implemented thereafter to simulate aerodynamic response for simple-harmonic input of displacement with suitable frequency.

该方法采用具有连续频谱分布且位移光滑的指数脉冲序列为CFD模型运动的输入，通过数值模拟得到作用在模型上的气动力。利用已知的输入和气动力建立起反映系统气动力特征的离散时间气动模型。

MRF approach ; train induced wind ; cross wind ; flow field ; aerodynamic forces of train ; aerodynamic forces of bridge

多重参考系法；列车风；横向风；流场；列车气动力；桥梁气动力

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 the full-scale aero-elastic model test, it is observed that there exist more than one interval of poor aerodynamic performance, and the non-symmetric erection sequence, while increasing the aerodynamic stability at the very places where aerodynamic performance of symmetric erection sequence is poor, performs worse in some other intervals with a vertical flutter phenomenon.

在全桥气弹模型的风洞试验中发现，采用对称架梁施工方法，在施工过程中会存在颤振稳定性最差的区间，并且这样的区间可能不止一个，而采用非对称架梁施工方法，固然在那些采用对称架梁施工时颤振稳定性较差的区间处提高了颤振稳定性能，但却在另一些施工区间中表现出比对称架梁施工更差的颤振稳定性能。

In the computation of aerodynamic forces, the present work is based on the work of Morino et al., but the following aspects are improved:(1) In computing the steady transonic aerodynamic load, the steady transonic nonlinear integral equation is solved by relaxation-iteration method in this thesis, instead of solving the time dependent transonic nonlinear integral equation, so that the computing time is saved greatly;(2) The influence coeifficients represented by volume integral are transformed to surface integral by using the Gaussian Theorem, so the analytical form of these coeifficients can be obtained and this leads to be more convenient to analyse and compile computer program;(3) The shock capturing method is used in every time step in present work, no shock moving term is added in the integral equation, so that it is more convenient and simpler to treat.

在气动力计算方面，本文基于Morino等人的工作，作了如下几方面的改进：（1）在计算定常跨音速流场（作为非定常绕流计算的初场）时，本文采用松驰迭代法直接求解跨音速定常非线性积分方程，而不是采用时间相关法求解非定常非线性积分方程，这样大大节省了计算机时；（2）将以体积分形式出现的影响系数化为面积分，并获得解析公式，这样便于分析和编写程序；（3）对运动的激波，本文通过在每一个时间步长上采用激波捕捉法而得到，而不是在积分方程中附加激波运动项，因而处理起来简单方便得多。

The linear aerodynamic forces of airship hull were calculated in terms of Munk airship theory. The linear aerodynamic forces of airship hull were calculated by Allen viscous cross flow theory. The fins linear aerodynamic forces were calculated by approach of panel method.

根据势流理论对飞艇艇身线性气动力进行分析计算，由于飞艇艇体是旋成体，故根据Allen的横流阻力理论对其所受的非线性气动力进行计算；尾翼的线性气动力采用有限基本解方法进行计算，非线性气动力用Polhamus-Lamar吸力比拟方法估算。

The results show that side force, lift and overturning moment obtained by simulation and by wind tunnel test are consistent. When train travels with certain speed, the aerodynamic force and overturning moment acting on passenger car running on bridge, embankment and flat will increase greatly as cross-wind becomes larger while those increase less when the train runs on cut. Under the condition of strong cross-wind, aerodynamic force and overturning moment acting on train traveling on bridge are the largest. So the train traveling on bridge tends to overturn compared with that traveling on other three kinds of railway conditions. Aerodynamic force and moment acting on train traveling on cut are the least.

研究结果表明：侧向力、升力和倾覆力矩数值模拟结果与风洞实验结果均吻合较好；车速一定时，随着侧风速度的增大，列车在桥梁、路堤、平地上运行所受气动力和倾覆力矩均急剧增加，而在路堑上运行所受气动力及力矩增加缓慢；当侧风速度一定的情况下，客车在高桥上运行所受到的气动力及力矩最大，因此，强侧风下列车在高桥上运行较容易发生倾覆事故；在路堑上所受到的气动力相对最小。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。