风洞

This thesis calculates effects of the Magnus and Saffman forces on the saltation height and distance of sand grains and vertical concentration distribution of Aeolian sand flow by combinations wind tunnel experiment data and motion model of saltating sand grains.

本文结合风洞实验数据、沙粒跃移运动学模型与风沙流的垂向分布模型，数值计算了Magnus与Saffman效应对跃移沙粒的跃移高度、跃移距离以及风沙流垂向质量浓度分布的影响。

Aiming at disjunction of microcosmic researches and macroscopical researches and status quo of theory basis researches of Aeolian sand movement near the sand bed, based on plenty of experiment data in wind tunnel, this thesis studies some microcosmic researches including the number of lift-off sand grains percent time percent sand bed area and relative movement parameters of saltating sand grains by combined methods of mechanical and statistical mechanical theories. Then, this thesis develops in advance a relation between the microcosmic researches and macroscopical researches in order to describe truly the theory model of some macroscopical physical variable of Aeolian sand movement.

本文针对当前风沙运动微观与宏观研究相脱节、准确描述近地面风沙运动规律的理论基础薄弱的现状，基于大量风洞实验数据，通过对沙床面单位时间单位面积起跳沙粒数、沙粒跃移运动过程中相关参数等微观问题的研究，力图建立风沙运动微观与宏观研究的联系桥梁，以期能够准确描述风沙运动宏观量变化的理论模型。

The number of lift-off sand grains percent time percent sand bed area Based on the lift-off velocity distribution function of saltating sand grain, this thesis gains the number of lift-off sand grains percent time percent sand bed area which ranges from 6796 to 8846900 number/(s·m2) by combination motion model of single saltating sand grain and some motion parameters of saltating sand grains and the flux of wind sand current from wind tunnel experiment.

单位时间单位面积沙床起跳沙粒数利用本文获得的沙粒起跳初速度分布函数，结合沙粒跃移运动学模型以及风洞实验中获得的沙粒跃移运动参数以及输沙量，反演出一定风场条件下单位时间单位面积沙床起跳沙粒数，变化范围6796-8846900个/(s·m2)，并满足。

Double-skin facade ; wind tunnel test ; wind load ; peak factor ; probability distribution ; computational fluid dynamics

国家自然科学；双层幕墙；风洞试验；风荷载；峰值因子；概率分布；计算流体动力学

A 2-D wind tunnel is built which is used to study tuthlent boundary layer on riblets as well as smooth plate surfaces.

设计并建造了一座二维低速风洞系统，用于壁面湍流边界层的减阻机理研究。

Vehicle models with smooth surface and riblets surface were tested respectively at various velocities and attack angles in a wind tunnel. Drag characteristic curves were acquired through tests.

在风洞中对具有光滑表面和脊状表面的航行器模型在不同风速和攻角下进行阻力测试，得到其减阻特性曲线。

A testing system for the characteristics of radiators was established.

为了对散热器的传热性能进行研究，建立了风洞测试系统。

The pollution accumulation results of post insulator and porcelain bushing in DC yard of converter station, natural contamination test station and wind tunnel were introduced. Artificial pollution tests were carried out on the post insulators with different sheds. The artificial rain flashover tests were also carried out on the bushings with different sheds profile. The shed configuration of insulator and porcelain housing such as sheds shape, core diameter, shed pitch were analyzed and compared.

分析了换流站、自然积污站和风洞试验中支柱绝缘子和直流设备套管的积污数据，对±500kV直流系统用不同伞形支柱绝缘子进行了全尺寸的人工污秽试验，进行了瓷套管人工淋雨试验，比较了伞形参数对支柱绝缘子和瓷套管污秽性能和淋雨闪络性能的影响。

The strain-gauge balance must be calibrated before it's using in the wind tunnel tests, and the precision and accuracy of the balance will be affected by the characters of the calibration system.

而应变天平在用于风洞试验前，必须进行静态校准，天平校准系统的性能指标将直接影响天平校准系数的准确性。

In this paper, wind profile modeling in the new boundary layer wind tunnel of Wind Engineering Research Center, Tokyo Polytechnics University, Japan, is introduced briefly.

首先简单介绍了日本东京工艺大学风工程研究中心新建的开环流低速边界层风洞中风剖面模拟的试验情况。

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％。