查询词典 fluid dynamics

Finally, the combination usage of parallel computing and MATLAB is studied, and is utilized on the parallel computing of Finite Element and Computational Fluid Dynamics.

集群监控管理系统自动监控整个并行计算系统的运行状况，把这些状态信息和异常情况保存于数据库，并提供图形化的接口，系统管理员可以方便的查看系统的运行信息、重新定制整个系统的结构。

The flow characteristic of undershot water is analyzed on the principle of fluid dynamics, and critical condition and theoretical calculation equation of the length of continuous flow are obtained.

根据流体动力学理论对下冲水的流动特性进行分析，得到了下冲水流保持连续性的临界条件，推导了连续流长度的理论计算公式。

This paper studies the main geometrical parameter such as angle, height, width, stagger and the upper width in dentation and trapezoid flow path, firstly, uses the single-phase numerical simulation of the computational fluid dynamics technique to analyse the influence of different geometrical parameter on discharge coefficient and flow state exponent of drip emitter. Secondly, uses the two-phases numerical simulation of CFD (1% sand content ) to analyse the influence of the above mentioned geometrical parameter on the contribution regulation of sand and anti-clogging performance. Thirdly, uses the PIV （ particle Tracking Velocimetry ） technique which can see the small-scale flow path to observe and test the trajectories and velocities of solid particles in labyrinth flow path, and analyses the basic factors which can influence the movement characteristic of solid particles and the flow state in flow path.

本文以齿形流道、梯形流道为主要研究对象，以流道转角、流道高，流道宽、偏差量及梯形流道上底宽为主要结构参数，首先应用 CFD 单相流数值模拟技术对不同结构参数灌水器流道水力性能进行模拟，分析了不同结构参数对流态指数和流量系数的影响，其次，应用 CFD 两相流（含沙量为1%）数值模拟技术分析了结构参数对含沙量分布规律和抗堵塞性能的影响，然后，应用 PIV 可视化测试方法测试了固体颗粒在流道内运行轨迹及速度，分析了影响固体颗粒运动特性及流道内流体流态的基本因素，最后，对上述流道结构形式通过模具加工及滴灌带试制，进行了标准化测试（ GB/T 17187-1997 农业灌溉设备滴头技术规范和试验方法与 ISO 标准 ISO /TC23 /SC18 /WG5N4短周期堵塞测试程序），测试结果验证了 CFD 模拟结果，并提出了迷宫结构流道灌水器的抗堵塞设计方法。

The finite difference method is one important numerical method for fluid dynamics.

其中有限差分方法是一种重要的数值计算方法。

Computational fluid dynamics method was utilized to the fiowfield numerical simulation of ultrafine stirred mill, the flowfield characters(velocity gradient, shear rate dispersion of flowfield and the dissipative force of viscosity and so on) of three kinds of stirrer(disc type, stick type and spiral type) were analyzed.

利用计算流体力学方法对超细搅拌磨机进行了流场仿真数值模拟，分析了盘式、棒式、螺旋式三种搅拌器的流场特性(速度梯度、流场的剪切率分布和粘性耗散率等)。

Five novel torsion-mirror optical actuators including double-beam thickness differential structure with single torsional axis, double flexible folded-beam structure with single torsional axis, double-beam vertical torsion comb structure with single torsion axis, four-beam differential compound-micromirror structure with double torsional axis and the combined structure of the four basis forms above, are brought forward. All of these devices could be fabricated by the same silicon micromachining process we have developed. The deformation compensation design with local enhancement for the thin torsional beam which is the key structure of these devices is also put forward to improve the reliability. The three-dimension solid model and two-dimension reduced order model of the torsion-mirror optical actuator are established and then the numerical simulations for evaluating the device characteristics of the statics, dynamics, electrostatic field, mechanical and electrostatic coupling, fluid and solid coupling are carried out to optimize the structure design. Furthermore, three optical fibre clamping structures which could be integrated monolithicly are designed and analyzed to improve the optical coupling capability. 4. Three flexible process flows combined with bulk silicon micromachining and surface silicon micromachining are brought forward to fabricate these novel single-crystal silicon or polysilicon torsion-mirror optical actuators by using the same lithography masks for both SOI wafer and regular silicon wafer. A series of important process experiments are carried out to optimize the process parameters and the process flows. Some novel and typical process phenomena which occurred during the microfabrication are analyzed and then the corresponding solutions are put forward. 5. A MEMS dynamic testing system which exploit blur image synthetic technique, stroboscopic image matching technique, stroboscopic mirau microscopic interferometry technique and microscopic laser dopper vibrometer technique is set up to measure three-dimension and six-freedom micro motions of any MEMS devices with nanometer resolution.

在对硅微机械扭转镜光致动器的光机电特性系统地理论研究的基础上提出了硅微机械扭转镜光致动器的结构设计准则。3、提出了单轴双梁厚度差分结构、单轴双柔性折叠梁结构、单轴双梁垂直扭转梳齿结构、双轴四梁差动复合微镜结构以及以上四种基本结构组合后的衍生结构等五种工艺加工技术兼容的新型的硅微机械扭转镜光致动器，对器件关键结构薄厚度、高耐疲劳扭转梁进行了局部加强的变形补偿设计，建立了器件的三维实体模型以及两维降阶模型，对提出的新结构硅微机械扭转镜光致动器进行了系统的静力学、动力学、静电场、力电耦合和流体固体耦合的建模仿真与优化设计，同时设计并分析了三种可实现单芯片集成的弹性光纤定位夹紧结构。4、提出了组合体硅微加工技术与表面硅微加工技术、兼容同一套光刻版图、可分别基于SOI 晶片和普通Si 晶片、适应于制造提出的各种新结构单晶硅和多晶硅硅微机械扭转镜光致动器的三套柔性加工工艺流程，开展了一系列重要工艺步骤的单项工艺试验，对工艺流程与工艺参数进行了优化，针对加工过程中出现的具有普遍意义的典型工艺问题进行了讨论和分析，并提出了解决方法。5、创新性地将模糊图像合成技术、频闪图像匹配技术、频闪Mirau 显微干涉技术与显微激光多普勒测振技术有机结合，建立起了一套周期运动测量与瞬态运动测量相结合、单点运动测量与全视场运动测量相结合、满足不同MEMS 器件各种动态测试要求的集成的MEMS 三维六自由度微运动精密测量系统。

The aerodynamics characteristic of the innovative control surfaces which are implemented on the flying wing aircraft with large aspect ratio were introduced, and elevon and split rudder were involved. And the control effects on three axis were analyzed basing on computetional fluid dynamics method. The concept of control volume was imported to introduce parameters-based method of control surfaces design. The control effect requirements of the control surfaces were also evaluated. The original design of certain aircraft's control surfaces was modified.

介绍了在该新布局飞机上采用的升降副翼和开裂式方向舵等新型操纵面的气动特点，并在计算空气动力学的基础上分析了其三轴控制效率，引进舵容量的概念提出了操纵面的参数化设计方法，基于飞机的可控性对各新型操纵面的操纵效率需求进行了评估，最终对某型飞机的操纵面初步设计进行了修正。

As a replacement of valve number 1 with Red Valve's Type A and pneumatic fail-safe system 700, valve number 3 has accomplished an improvement in the fluid dynamics of the system.

作为1号阀的替代品，美国红阀公司A型夹管阀和无故障气动系统700，也就是左图中的3号阀，极大地改善了流体介质的流动性。

This paper discusses this topic under consideration of the group structure of finite difference scheme in traditional fluid dynamics.

这种趋势的背景源于流体力学问题本身的强非线性，一般经典的数学手段难于处理，需要引入能对付大范围强非线性问题的数学手段。

Objective To study the application of computational fluid dynamics in designing of artificial heart.

目的 探讨计算流体动力学方法在人工心脏设计中的应用。

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。