动力动量

An aerodynamical urban canopy scheme is incorporated into the fine town boundary layer model. The scheme contains drag effect of urban buildings on flow and effect of building morphology on urban turbulent activity and momentum transfer.

文中将建筑物动力冠层方案引入到城市边界层精细模式中，该方案描叙了城市地区建筑物对气流的拖曳作用以及建筑物形态对城市地区湍流活动动量输送的影响。

For the plane wave of laser without pulse shape, we derive the express of electron trajectory by the relative Lorentz and energy equations. Note that the orbit of electron becomes a "fat-8" in the average rest frame. For the plane wave of Gaussian laser, we may know that, through relative Hamilton-Jacobi equation, electrons are accelerated in the front of pulse and decelerated backward. Whereas for the non-plane wave of Gaussian laser, we solve the Lorentz and energy equations by fourth order Runge-Kutta method.

对于无脉冲形状的激光平面波是从考虑了相对论效应的Lorentz方程和能量方程出发，得到了电子的运动轨迹方程表达式，在纵向平均速度参照系下该电子的轨迹呈现"8"字形；对于高斯型单色激光平面波是从相对论Hamilton-Jacobi方程出发，得到激光平面波在脉冲前沿加速电子而脉冲后沿减速电子，电子能量增益为零；而对于高斯型单色激光非平面波是从拉格朗日运动方程和能量方程出发，通过四阶Runge-Kutta法数值求解，得到电子在纵向有质动力、横向电场作用下加速电子，最后在强大的横向有质动力作用下从脉冲侧面散射出去，可以获得很大能量增益本文得到了相应的电子瞬时动量解析表达式。

An analytical model was built up on the jet deflection in the crossflow by applying the theorem of momentum, which takes full account of mixing between the upstream fluid and burner jet, and of the total pressure difference between the two sides of the jets. Through analysis of this model, experimental study and numerical simulation, effects of the nozzle spacing ratio, width of the furnace corner, width of the nozzle and imaginary circle diameter on the aerodynamic field in the furnace were obtained.

本文综合考虑了炉内旋转气流与燃烧器射流的混合和燃烧器射流向火侧与背火侧的全压差等因素，应用动量定理建立了横向气流中射流偏转的分析模型，并结合冷态模化试验和数值模拟计算，得到了燃烧器间隙率、炉膛切角、喷口宽度和假想切圆直径等因素对炉内空气动力场影响的规律。

The sea ice dynamics mainly includes the sea ice motion, breakup, rafting and ridging under the driving of ocean and atmosphere.

海冰动力学主要研究海冰在海洋、大气的动力强迫下的运动变化、动量传输及其断裂、重叠和堆积等动力学特征。

This paper describes and compares 4 streamtube models (single-disk single-streamtube, double-disk single-streamtube, single-disk multi-streamtube and double-disk multi-streamtube models) based on the momentum theory for the hydrodynamic performance prediction of the vertical-axis variable-pitch turbine that may be employed to tap tidal stream energy resources, especially for the prediction of the overall turbine power coefficient.

以潮流发电水轮机的设计为研究背景，分析和总结了基于动量定理方法的四种流管模型(单盘面-单流管模型、双盘面-单流管模型、单盘面-多流管模型和双盘面-多流管模型)在竖轴变攻角水轮机的水动力性能计算中的应用，特别是能量利用率预报方面的应用。

The semi-rigid wake model and the present calculation method were used to study two wind turbines in the wind tunnel, it was concluded that the results were closer to experiment data than that from the element/momentum theory, and aerodynamic performance of HAWT can be analyzed precisely, in particular, in the range of high tip speed ratio.

对两个风洞中实验的风力机模型进行了计算，结果表明，利用所给出的模型和计算方法比叶素/动量理论更加接近实验数据，并且在较大尖速比范围内可精确地分析水平轴风力机的空气动力特性。

By considering the finite spread in beam longitudinal momentum and the effect of finite space-charge field of the electron beam,the dispersion relation of IRL instability is derived ,and the growth rate of IRL wave and the linear damping rate of the space-charge wave are also got.

利用动力学理论对一种新型自由电子激光──离子波纹激光进行了研究，考虑电子束的纵向动量离散和空间电荷场效应，导出了IRL不稳定性色散关系，求得了IRL辐射波的增长率及电子束空间电荷波的线性阻尼率，并对其进行了讨论，得到了一些结论。

First we showed that high latitude thermosphere's response to heat sources is different from that to momentumn sources, which can be generally explained by geostrophic adjustment, with the main energy of the momentumn sources remained in the local region, and the main emergy of the heat sources transported to mid and low latitude.

首先把动力气象学中大气适应的方法应用到极区热层大气，分析了热层大气对动量源和热源的不同响应机制，认为极光区加热源是引起中低纬热层大气扰动的主要因素。

We have pass the certification of the ISO9001 and ISO9002,at present we e are applying for the quality certification of the international TS16949 3 We improve the dynamo with the science, and have serial high accuracy inspection instruments which can exam the process whenever, as Germany spectra direct read spectroscopes, line measurement instruments ,gold analysis instruments, air movement instruments, ultrasonic testing equipment, all-around microscope .

大川活塞以科技提升动力，拥有系列高精度检验设备，可在各个环节对产品进行实时检验，如德国 spectro 直读式光谱仪，型线测量仪、金相分析仪、气动量仪，超声波探伤设备，万能工具显微镜。

This is not an ordinary box, which is used as a background picture of the dialog box, very pretty.

详细说明：这可不是一个一般的对话框，它是用图片作为背景的对话框，非常好看。

Conceal me what I am,and be my aid for such disguise as haply shall become the form of my intent.

遮掩我的身份，帮助我，我的面具将成为我的目的。