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Furthermore the performances of heat transfers including corrugate plate, tube and fin-tube were compared under the same conditions. The results show that when the air frontal velocity is between 2.45 and 4.1m/s, the overall heat-transfer coefficient of plate heat exchanger ranges from 100 to 160 W/m^2/ equal to one sixth of that of fin- tube cooler based on tube outside area, which is about 70% higher than that of tube cooler. The volumetric heat transfer capacity of plate cooler is 1.5 times as that of fin-tube cooler and 15 times as that of tube cooler. The heat transfer capacity of per unit power of plate cooler is 5.5 times as that of tube cooler and similar results for fin-tube cooler.

在相同工况下，比较了波纹板式、光管式和翅片管式空冷器的性能指标，结果表明：迎面风速在2.45~4.1m/s之间，波纹板式空冷器传热系数达到100~160W/平方公尺/℃；约比光管式提高70%，但只有以管束外表面为基准的翅片管式传热系数的六分之一；板式空冷器单位体积换热量约是翅片管式空冷器的1.5倍，是光管式的15倍；板式空冷器单位功耗换热量约是光管式空冷器的5.5倍，而翅片管式空冷器与光管式空冷器则相差不大。

Based on the theory of cavitating flows,the definition of supercavitation ,the main idea of reducing drag by ventilated cavitation and the principle of supercavitation torpedo are introduced.

文章从空泡流理论出发，介绍了超空泡的定义、超空泡减阻的基本思想和超空泡鱼雷的工作原理，并分析了超空泡技术研究中的关键问题和未来发展趋势

This paper briefly introduces the current development of supercavitating torpedoes in the world,and explains some confusable terms,including cavity,supercavitation, natural supercavitation ,air supercavitation and cavity number.

在简要回顾各国超空泡鱼雷发展概况的基础上，解释了几个易混淆的与空泡有关的新术语(空泡、超空泡、自然超空泡、通气超空泡和空泡数)，分析了超空泡的形成机理和特点，详细阐述超空泡鱼雷在总体结构和性能、动力推进、控制系统和弹道形式等方面的技术特点，概括超空泡鱼雷与普通鱼雷在结构外形、流体动力布局、系统组成和工作特性等方面的不同之处。

A high-speed camera is used to visualize the flow structures,and Laser Doppler Velocity is employed for velocity measurement.The osculations are conducted on the two-dimensional hydrofoil section,based on a single-fluid model of the cavitation:the liquid/vapor mixture is considered as a homogeneous fluid whose eompsition is regulated by mass tranfer equation.The RNG k-ε turbulence model with modified eddy viscosity coefficient is used for computing,and the coefficient is related to the vapor and liquid densities in cavitated regions for simulating the cavitating flow.

实验采用高速录像技术观察了云状空化随时间的结构变化，应用 LDV 测量了云状空化条件下翼型周围的速度分布；采用 N-S 方程和基于空泡动力学方程的空化模型计算了绕水翼云状空化流场，湍流模型采用了 RNG k-ε方程，为了改善空化流动的计算精度，引入了一种与空化区域水汽相密度相关的系数，对湍流涡黏性系数进行了修正。

The osculations are conducted on the two-dimensional hydrofoil section,based on a single-fluid model of the cavitation:the liquid/vapor mixture is considered as a homogeneous fluid whose eompsition is regulated by mass tranfer equation.The RNG k-ε turbulence model with modified eddy viscosity coefficient is used for computing,and the coefficient is related to the vapor and liquid densities in cavitated regions for simulating the cavitating flow.

实验采用高速录像技术观察了云状空化随时间的结构变化，应用 LDV 测量了云状空化条件下翼型周围的速度分布；采用 N-S 方程和基于空泡动力学方程的空化模型计算了绕水翼云状空化流场，湍流模型采用了 RNG k-ε方程，为了改善空化流动的计算精度，引入了一种与空化区域水汽相密度相关的系数，对湍流涡黏性系数进行了修正。

In orde to obtain system optimization in high efficiency production and operation safety, the microcosmic problem of goaf treatment was brought into the creative design of mining method and the synergism of two problems was studied. Firstly, in view of the occurrence characteristics and mining conditions of catacalstic ore section of orebody No. 105 in Gaofeng mine in Guangxi province, considering the adaptability to different scale goafs in the ore section, based on mining environment reconstructing idea and continuous mining mode, a new mining method (mining environment reconstructing non-pillar sublevel-strip continuous mining method) was put forward. Then, some repr, esentative goafs were selected and their stabilities were calculated by discrete element method on the basis of differences of goaf scale, surrounding conditions and situ stress field. At last, the mining layout was adjusted on the basis of goafs stability analysis and the goafs were adjusted as a part of cutting engineering, blasting space or stope, so as to determine all kinds of goafs treatment schemes.

摘 要：为在生产高效和作业安全上取得系统整体最优，将碎裂矿段的空区处理微观问题纳入采矿方法创新设计宏观问题中，开展2种问题的协同研究：首先，针对广西高峰矿105号矿体碎裂矿段的赋存特点和开采技术条件，考虑对各种规模空区适应性，基于采矿环境再造和连续采矿理论，提出采矿环境再造无底柱分段分条连续采矿法；然后，根据采空区规模、围岩状况和原岩应力场等条件的差异，在所有采空区中选择具有代表性的空区，运用离散元程序对其稳定性进行计算分析；最后，在稳定性分析的基础上，灵活调整开采布局，将采空区调整为部分切割工程、自由爆破空间或采场，从而确定出各种规模空区的处理方案。

Themotion equations of a bubble near a plane wall have been established with the lift forceand wall effects on the drag force taken into consideration.

我们在全面考虑壁面对空泡运动粘性阻力和升力影响的基础上，建立了空泡在近壁区内的运动方程，计算结果表明由于壁面的存在将阻滞空泡沿水流方向和垂直水流方向上的运动，即有滞留空泡在空化形成点，减缓空泡逸离空泡发生区的作用。

Based on Wavelet Packet Analysis and Smoothed Pseudo Wigner-Ville Distribution, the experiment data is time-frequency analyzed. The experimental results indicate that the amplitude of the laser-induced acoustic waves increases with the laser energy; the frequency coverage is from 0 to 150 KHz, and in the meantime there is a peak located at about 25 KHz. In addition, the spectrum and the peak of frequency are basically stable in spite of the change of laser energy and target texture.

从基本的空泡动力学理论出发，推导了空泡各特征参量之间的关系，进而对空泡动力学模型进行了修正；采用有限差分法对空泡脉动进行数值模拟，得到了空泡脉动特性随液体粘性、空泡含气量、表面张力以及可压缩性的变化规律；实验上采用光偏转测试装置探测了激光空泡脉动以及空泡溃灭的细节过程，进而分析了液体粘性和作用激光能量对空泡脉动周期、泡半径及泡能等特征参数的影响。

Assuming fluid is and viscid and slightly compressible, bubble collapse near rigid boundary and free surface is simulated, displaying characteristics such as formation, penetration and impact of reentrant jet as well as vortex ring and bubble rebound.

采用粘性、微可压流体模型，数值模拟了空泡在刚性边界和自由面附近溃灭及空泡溃灭后流动的发展，显示了空泡溃灭过程中的凹陷射流形成、空泡贯穿、射流冲击、涡环的形成和空泡回弹等流动特征，提出空泡回弹的另一种机制是凹陷射流冲击形成的旋涡。

Finally, the researchers 51 the children's speech at age 3, using a standardized language test. The only predictors of high scores on the test were the mother's level of education, the 52 of child care and the number of different words the father used. The researchers are 53 why the father's speech, and not the mother's, had an effect."It's well 54 that the mother's language does have an impact," said Nadya Pancsofar, the lead author of the study. It could be that the high-functioning mothers in the study had 55 had a strong influence on their children's speech development, Ms. Pancsofar said, Or it may be that mothers are 56 in a way we didn't measure in the study.

大家可以看一下这十个空五个空是考察动词的，两个空考察名词，两个空考察形容词，还有一个空考察的是副词，可见动词占了一半的比例，而且动词的考察不仅仅考察原形，这里面考察的都是过去时或者是它的ing动名词或者是进行时的一个形式，所以说大家在选择的时候一定要小心，除了根据它具体的单词的含义和上下文的内容来选择之外，还有判断这个单词的形式是不是跟我们这个空按照语法规则是吻合的，所以大家做题一定要小心。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。