对流

The intensity is less and depth is higher comparing with ones of Yangtze River Basin in the Mei-Yu period and quasi-stationary front rainstorm in South China.

混合云团与东移的高空槽云系相遇并叠置的大到暴雨过程，镶嵌于回波中的对流单体是造成强降水的直接系统，其尺度只有10～20km。

During the four years study on the project, we develop a dynamical forecast model that describing the subtropical ridge surface. A new theory on the role of the land-sea thermal difference on the formation of the Subtropical High is advanced. It is concluded that in the summer subtropics over each continent and its adjacent ocean LO, SE, CO, and a double-dominant heating from west to east compose a LOSECOD heating quadruplet. The influence of the Eurasia continent on SH varies according to the seasonal variation. From the ideal numerical simulation it is shown the important role of the Eaiuan continent and the huge topography on the mechanism of formation and mantanence of the SH during the summer. It is verified by the numerical simulation that the extension of the subtropical continent into the tropics greatly enhances the " East Asian monsoon". Through the Rossby energy dissipation theory it is verified that the deep latent convective heating induces the onset of the South China Sea monsoon over the Bay of Bengal. The relationship and mechanism between the precipitaiton over the East Asia and the Subtropicla high is illustrated by the data. It is also found the close phase lock between the east-west shift of the SH and the disturbence of the east wind belt over the tropical troposphere. The interaction between the structure and activity feature of the SH and the Meiyu over the Yangtze-Huaihe river valley is revealed from the data. The numerical simulation verified the impact of the different SH pattern on the path of the typhoon.

本项目的研究发展了描述副热带高压脊面变化的动力模型，提出了夏季副热带地区四叶型非绝热加热分布型及相应环流拼图的创新理论；明确了大陆尺度的海陆热力差异在副热带高压形成中的作用；指出欧亚地形对副热带高压和气候的影响随季节变化而变化，通过数值试验证明春季青藏高原的感热加热对亚洲夏季风的爆发地点起了&锚定&的作用，进一步证实了副热带高压断裂和亚洲夏季风的最早爆发地点发生在孟加拉湾东岸；利用Rossby波能量频散理论证明了孟加拉湾深对流潜热释放诱导南海季风爆发的机制；揭示了东亚季风降水的季节内变化与西太副高的关系及机理；揭示了西太副高与东西风带中扰动之间的相互作用过程，指出西太副高的东西活动与热带对流层上空东风带扰动和中纬度西风带扰动的移动和锁相密切相关；研究了夏季淮河流域梅雨期间副高结构和活动特征及其与江淮暴雨的相互作用；验证了不同副热带高压形态对台风路径的不同影响；通过数值试验证明了欧亚大陆和青藏高原等大地形对副热带高压形成和维持的重要作用。

A simple zero-order flat model is usually used to characterize the well-mixed convective boundary layer under clear sky.

作者中文名：卢萍；郑琴；宇如聪；穆穆摘要：晴天充分混合的对流边界层中常采用相对简单的零阶近似平板模式。

In the third type, the double-ring cloud wall is formed as a result of the development of cumulus convection inner region of typhoon into a well-closed inner cloud wall. The inner wall usually lasts for a period of time and then rapidly disappears.

还有一类双环云墙的形成是由台风眼内积云对流发展而演变为环状闭合内云墙的，这类台风的内云墙维持一段时间后即消散。

Moreover, blobs may move too close to the boundary because of advection errors or other numerical errors. It may cause serious fluctuations in evaluating the strength of the vortex sheet. In order to reduce the fluctuations, these near-wall blobs are also manipulated in use of the concept of "residual vorticity". Finally, we apply the so-developed solver to a simulation of the flow past an impulsively started circular cylinder at different Reynolds numbers.

此外既有涡泡也可能因对流或其他数值误差造成过於靠近边界，因此我们也设计一专门处理过於靠近边界涡泡之方法，以其他计算元素取代这些涡泡，降低进入物体内部之环量，进而降低涡片强度计算上的扰动。

When the reconstructed wind approachs the original one, it means the partitioning process is successful and the calculated stream function and velocity potential is accurate.

目前，对风场进行有效分解的方法是对有限区域里的流函数和速度势进行求解，然后对流函数和速度势求导得到对应的无辐散风与无旋转风。

It is shown that the modified model can predict successfully the characteristics of cavitation and the detailed process of the cavitation shedding. Values of n in the modified coefficient are found to have a strong influence on the cavity length, the vapor volume, the lift and drag force, but no significant effect on the frequency distribution of the dynamics around the foil is observed.

通过与实验结果的对比表明，修正后的模型可以更准确地捕捉云状空化区域的空穴形态和空泡脱落的非定常细节；密度函数中指数n的选取对计算所得的空穴长度和升阻力均有影响，然而对流场动力特性的主要频谱分布影响不明显。

Unlike soldering methods, which rely on ovens for heating, vapor phase reflow delivers consistent heating across the board.

印刷电路板装配方法是典型的红外对流再流焊，或气相再流焊。

The interior flow field of the deep－well pump is studied with Particle Image Velemetry technology. The effects of flow field on motion rule of valve and the effects of interior structure on flow field are analyzed.

林盛应用粒子成像测速技术对深井泵泵内流场进行了研究，分析了流场对泵阀运动规律的影响以及泵内结构对流场的影响。

In addition, the heat transfer coefficient in the case of low velocity jet flow in the beginning.

整体而言空间内部与加热板温度随时间的增加，所造成热对流系数逐渐下降。

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％。