内流

As a downstream piping system when the valve opens, reflux valve, when closed, the main medium used to prevent backflow to prevent the pump and drive motor reversal, as well as a container medium discharge; currently the most commonly used is the valve flap around the body Swing Pin rotation flap valve and the valve body along the vertical axis to move lift check valve, but the above two kinds of structures exist in the valve closed, medium speed back quickly from the largest drop to zero, inlet side of the pipe resulted in the rapid pressure rise, resulting Proportional Pressure Reducing Valves in damaging effects on the piping system of water hammer phenomenon, it is generally a diameter of valve production of 50 ~ 500 mm.

止回阀作为管道系统顺流时开启，逆流时关闭的阀门，主要用于防止介质倒流，防止泵及驱动电机反转以及容器内介质泄放；目前使用最普遍的是阀瓣围绕阀体销轴旋转的旋启式止回阀和阀瓣沿着阀体垂直中心线移动的升降式止回阀，但以上2种结构的阀门均存在关闭时介质倒流速度从最大迅速降为零，致使管道进水管一侧内压迅速升高，从而产生对管路系统有破坏作用的水锤现象，所以一般止回阀生产口径为50～500 mm。

Taking water-jacket of 226B diesel engine as the practical objective, the calculation in void fraction and the velocity filed of the water jacket were made.

最后以226B 型发动机水腔为工程应用对象，计算出了水腔内的空泡份额分布和水腔内的流度分布情况。

By analyzing the results of simulation and experiment, a series of new phenomena were found. There is an inner boundary within the rotational flow field of cyclone. The velocity head is zero on the inner boundary.

通过对仿真结果的分析，并结合试验数据，揭示出一系列新的现象，主要归纳为：旋风分离器内的旋转流场中存在一内边界，其速度头为零。

Two test pieces with satin surface and rib surface were designed under conditions of different distribution of heat flow density and different air flux.

我们对两块冷板实验件(内表面光滑与内表面带肋)就热流均匀分布与热流局部分布、不同空气流量的情况下进行了试验研究，然后采用三维通用形式N-S控制方程，建立适于工程应用的冷板三维流固耦合传热过程的数理模型。

On the basis of this model, combined with potential flow for expressing burden flow, considered with gas-solid heat exchange and main chemical reaction in shaft furnace, Comprehensive two dimensions mathematics model of shaft furnace is set up for analyzing flow, heat and mass transfer in furnace.

并在此基础上，结合反应固相流动的势流模型，综合考虑气固传热和竖炉内的主要化学反应，建立了竖炉二维综合数学模型，对炉内流动、传热及传质过程进行了解析。

Using RFPA2D-Flow stereo-gasses coupled system to simulate the process of gas draiange in lower air permeability coal seam by loose blasting,it interprets that loose blasting is a effective ways to increase air permeability in low air permeability coal seam .

运用RFPA2D-Flow固气耦合系统模拟了松动爆破抽放低透气性煤层内瓦斯的过程，解释了爆破松动是增加低透气性煤层透气性的有效途径，本文对松动爆破前后抽放过程中煤层内瓦斯压力和瓦斯渗流场的变化规律进行了数值模拟对比，为进一步理解瓦斯抽放、松动爆破增透机理等提供理论基础和科学依据。

Through the details simulation calculation of typical operation conditions of turbine, some conclusions are showed: the design of the overflowing parts is appropriate; the flow in the draft tube is smooth in the optimal operation conditions, the rotation direction of the vortex band is reversed to the runner in the large flow, and the rotation direction of the vortex band is identical to the runner in the small flow.

通过对水轮机典型工况点的详细计算分析，可以看出：各过流部件的设计符合设计要求；同时在最优工况下，尾水管没有明显的偏心涡带，在大流量工况下，尾水管直锥段内有与旋转方向相反的涡带；在小流量工况下，尾水管直锥段内有与旋转方向相同的涡带。

To investigate the pressure drop due to the friction between gas-solid suspension and CFB riser wall and its effect on the measurement of average solids holdups by pressure transducers,models for predicting the pressure drop and the solids holdup were developed.

为确定气固提升管充分发展段的摩擦压降及其对颗粒浓度测试的影响，提出了充分发展段内气固两相流与管壁间摩擦压力降的计算模型，由此获得充分发展段内真实颗粒浓度的计算公式；同时在两套提升管实验装置上对压力梯度分布和局部颗粒浓度进行了系统测试和对比分析。

In other words, regional mean runoff may be considered as the difference values between mean rainfall and infiltrations over a given heterogeneous land surface region, and the mean infiltration for the region may be calculated from two parts of infiltrations for saturation and non-saturation areas.

换言之，区域内地表产流率可视为区域平均降水量与区域平均的土壤下渗量之差值，而区域内土壤的平均下渗量又可分为非饱和区和饱和区两部分的下渗量来分别计算。

The flow resistance of Ice slurry increases if the pipes obliquity increases. That means the ice slurry that in the level pipe has the largest flow resistance, the reason is: the gravitation make the flow became more and more foul-up, accordingly, lead to the increase of flow resistance. Sixthly, introduced all of the preparative tasks before we began the experiment, because we met many problems during the test, we had our own methods which could solve these problems. In this paper, problems and these methods were introduced.

随着管道倾角的增大，二元冰的摩擦阻力减小，也就是说相同条件下水平管道内的摩阻最大，这是因为重力的影响导致管道内二元冰和乙二醇分层现象更加明显，从而导致紊流程度增大，最终使得摩阻增大；第六，对二元冰蓄冷空调系统运行前的准备工作进行了介绍，由于在试验过程我们遇到了很多问题，针对这些问题，我们有自己的方法和解决办法，本文介绍了这些问题和相应的解决办法。

By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.

到它被攻陷的时候，里面多数的犯人是写了反对政府贪污文章的作家。

The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.

在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色，卵在发育96h后卵基本全部孵化。