辐合

The low-level wind field displayed cyclonic character on the north part of the squall line, whereas on its south part the wind field pattern was anticyclonic, with clear convergence of westerly and southeast inflows in between.

飑线不同位置的水平风场结构有很大不同，在飑线北端，低层是气旋性辐合风场，飑线南端是反气旋性辐合风场，而中部沿强对流窄带的前部是偏西和东南风的风场辐合。

The mechanism was similar to the equivalent barotropic warm core structure. The Conditional Instability of the Second Kind was the primary mechanism of development and maintenance for MCSs in case 2005. As the MCSs intensified and persisted, the latent heating was highly efficient in producing significant enhancement of Mei-Yu front systems. The LLJ intensified by Coriolis acceleration of ageostrophic wind was induced by the effect of latent heat release. The LLJ and the effect of latent heat released reinforce each other in convection system through a positive feedback process.

综合而言，2005年个案中梅雨锋面结构为垂直近乎不倾斜的浅系统，槽线系统不明显，锋面水平温度梯度微弱，低层具有强水平气旋式风切，较似正压系统，个案中MCS发展及维持机制，主要是透过CISK 过程来维持；其过程是由於低层锋面带上之辐合激发对流发展，对流潜热释放造成局部气压梯度增强，因而增强地转风；而潜热释放亦有利低层辐合之增强，产生非地转风，再透过科氏加速增强西南风，使LLJ增强，形成一正向的回馈作用。

And the perfect Q-vector was applied to diagnose a heary rain process for August 3～5, 1996. The results showed that there were more advantageous using the perfect Q-vector, and suggested that the perfect Q-vector could clearly reveal the system development of the heary rain; the divergence center or line, the divergence field and the frontogenesis function field of the perfect Q-vector could be used to locate the heary rain area; the center magnitudes of the perfect Q-vector divergence field and the frontogenesis function field could be signified the intensity of the heary rain.

结果表明，完全Q矢量能较清楚地揭示暴雨天气系统的演变；考虑了湿过程的完全Q矢量在暴雨的诊断过程中显示了其更大的优越性；定性而言，完全Q矢量散度的辐合中心或辐合线、散度场和锋生函数场有助于确定暴雨的落区，暴雨区正好落在低层完全Q矢量散度场辐合中心和锋生函数场正值中心之间；定量而言，低层完全Q矢量散度场辐合中心和锋生函数场正值中心大小对暴雨强度有显著的指示作用。

Numerical tests are also conducted to investigate the microphysical effects to the mesocale convective systems. The evaporation of raindrops can strengthen the surface "cold pool" to decease the temperature of rainfall center. The condensation of vapor can lower the air pressure and increase the convergence and updraft so that the convective echo develops stronger. The melting of graupel can cool the air to restrain the convective activity. The falling of precipitation particles can increase the downdraft and induce the outflow nearly the surface. The effect of condensation is the most important among all the microphysical processes. It can change the whole structure of cloud system.

微物理过程对对流系统发展和维持有重要作用：强降水的雨滴蒸发过程会加强"冷池"效应，同时增强了雨带南侧原有的地面中尺度辐合线；凝结潜热在低层诱发了与回波相应尺度的中尺度低压，增强了辐合和上升运动，促进对流发展；霰的融化吸热通过冷却大气会不利于气压下降、气流辐合抬升等过程，降低对流不稳定能量，减缓对流发展；重力拖曳使气块冷却降温，降低对流不稳定能量，并且使低层的气压升高、气流辐散，在近地面附近产生出流，加强地面中尺度辐合线的强度。

The results suggest that the squall line occurred under the favorable weather conditions.

结果表明：飑线是在有利的天气形势下发生的，飑线上强风暴的强度大、高度高；飑线速度剖面图中显示有低层辐散、中层辐合、高层辐散的特征；垂直累积液态水含量迅猛增加到比较大的数值对冰雹预报有很好的指示意义；在冰雹指数产品中以强冰雹概率大于30%作为冰雹预警门限则有较好的效果；边界层辐合线起到了触发对流和加强对流的作用。

In the initial stage, the convergence of the low layer was stronger than that of the upper layer of the boundary layer, and the rotation of the boundary layer flow was weak, so a convergence line of the boundary layer was one of important factors to trigger convection.

MCS初期边界层低层的辐合强于边界层高层辐合，边界层气流旋转作用较弱，边界层辐合线是对流触发的重要因素之一。

The flow field construct of meso-β cloud clusters which bring the heavy-hard rainfall in northeast plateau is that the low level cloud cluster is located in the south of converging region, the southern low level influx converged in the cloud cluster and have some affection on the setting up of the rainstorm in the low level. In the middle level, the cloud cluster is lied in near the westerly trough and the southwest airflow ahead of the trough constantly transmits water vapor to the cloud cluster. In the high level, there are a pair of high and low pressure centers around cloud clusters and are obvious divergence airflow, and there is weak ageostrophic high level outflux along pressure force.

产生高原东北部地区大到暴雨天气过程的中—β尺度云团的流场结构特征是：在低层，云团位于辐合区的南部，低层的偏南低空入流在云团内辐合，对大到暴雨的形成有一定的作用；在中层，云团位于西风带低槽附近，槽前的西南气流不断地给云团输送水汽；在高层，云团附近有一对高、低压中心，为明显的辐散气流，沿气压梯度力方向有强度不强的非地转高空出流。

With the fluid-solid coupling of train oil tank clue to train speed increase, the fluid-solid coupling modal analysis of G70B oil tank is calculated by NSYS. The finite element model of fluid-solid coupling system is set up. The fluid-solid coupling modal analysis of G70B oil tank is done for light oil tank train under different kinds of loads and its natural frequency and modal shapes are obtained.

针对列车油罐因列车提速导致液固耦合作用突出的问题，运用ANSYS软件对轻型油罐车G70B型罐体的液固辐合模态响应进行实例分析和计算；建立车载油罐的液固辐合系统有限元模型；对轻型油罐车G70B型罐体进行在不同贮液比时的液固福合模态分析，得出固有频率和模态振型图。

The severe storms on the squall line had large radar reflectivity and high tops of echoes. There was a divergence at lower level, a convergence at middle level, and a divergence at upper level in the velocity cross section of the squall. The VIL (Vertical Integrated Liquid water) of the storms increased rapidly to a large value, which is a good indictor of hailstorm. When the probability of severe hail is larger than 30% according to the hail index products, a hail storm is very likely to happen. The convergence line in the boundary can trigger and intensify convections.

结果表明：飑线是在有利的天气形势下发生的，飑线上强风暴的强度大、高度高；飑线速度剖面图中显示有低层辐散、中层辐合、高层辐散的特征；垂直累积液态水含量迅猛增加到比较大的数值对冰雹预报有很好的指示意义；在冰雹指数产品中以强冰雹概率大于30%作为冰雹预警门限则有较好的效果；边界层辐合线起到了触发对流和加强对流的作用。

In order to develop and modify Gregory scheme for cumulus convective parameterization,we make the improvement as follows:(1) The large-scale moisture convergence is taken into account and the organized inflow,which occurs in the area of large-scale moisture convergence and is directly proportional to it, is added to turbulent airflow.(2) The influence on saturation vapor pressure exerted by supercooled water is taken into account and the initial mass flux is adjusted. Based on diagnosis of the air heating and moistening, the downdraft airflow is adjusted.(3) Based on the character of our country heavy rainfall,which usually occurs in the mixed cloud consisted of stratocumulus and cumulus, the process of excessive convection is restrained by organized outflow in the top of cloud and improving downdraft current and by reducing the evaporation of rainfall and release of latent heat.

为了改进和发展Gregory积云参数化方案，(1)考虑了大尺度水汽辐合对积云对流的影响，即在混合卷入中加入有组织的卷入，让有组织的卷入存在于有大尺度水汽辐合的层次上，并且与大尺度水汽辐合直接成比例；(2)考虑了过冷水存在对饱和比湿的影响，调整了初始的质量通量，并且根据对大气加热加湿的诊断，调整了大气向下拖曳的强度；(3)根据我国降水多由层状云和嵌入其中的对流云混合产生的这一特点，对于过强对流过程进行抑制，在云顶加入有组织的卷出，同时加大向下拖曳的强度，减少蒸发以降低潜热的释放，抑制过强对流的发生。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。