内流

The converter combines the advantages of the PWM technique and soft-switching technique, the PWM is effected all over the whole loads range, and soft-switching is effeted only in the switching transition period, the ZVS of leading-leg is achieved by using the energy stored in leakage inductor of the transformer and the output inductor, the ZCS of lagging-leg is achieved by using a blocking DC capacitor, the ZVS and ZCS are achieved for the whole load ranges (5A~250A).

控制电路采用相移控制方式，综合了PWM控制和软开关技术的优点，在大范围内实现PWM控制，而在功率器件换流期间实现软开关换流，其中超前桥臂利用变压器的漏感，实现了零电压开关，滞后桥臂利用隔直电容，实现了零电流开关，并且整个变换电路能在（5A~250A）的范围内实现软开关工作条件，满足弧焊电源负载变化大的特点。

Based on the study of gas solid flow field in blowpipe of BF with oygen enriched PCI, the oxygen and coal concentration distribution inside the blowpipe were simulated and discussed, including the influence of position and inserting angle of the oxygen coal lance, the pattern of the oxygen enriched jet, as well as grain size of the coal.

在对高炉局部富氧喷煤直吹管内气固两相流流场研究的基础上，对直吹管内氧和煤粉的浓度场进行了数值研究，包括氧-煤喷枪的插入角度和枪位、局部富氧射流的漩流数以及煤粉粒度的影响。

At half normal delivery the results confirm the already known instability of flow both with time and between blade passages and suggest that cinematograph recording of the relative flow in all the passages at the same time would be desirable.

在二分之一正常流量时，需借助电影摄影机对所有流道内的相对流动进行记录，叶片流道内间流动随时间的不稳定性得到证实。如果需要，请联系本人。

The dynamic flow profile inside a conically shaped column for preparative liquid chromatography was studied by using a self-made device where the movement of acolored sample in the column could be observed clearly and truly.

利用自制的台锥形色谱柱内谱带流型可视化研究装置，对台锥形色谱柱内样品谱带的流型进行研究。

Comparing with real engineering, analyze the experiment and simulation results, the conclusion is that the mixture model can simulate the flow field of gas-liquid two-phase well; the effect of plain plug flow aeration is better than circumvolve plug flow aeration's; for the same plug flow aeration , the effect of 20m/s aeration is better than 10m/s's and

结合实际工程的运行，对实验结果及模拟结果进行对比分析，结论为：采用混合模型能够很好的模拟曝气池内气液两相流的流场；平移推流式曝气比旋转推流式底层曝气的曝气效果好；在同种曝气方式，相同工况下，20m/s的曝气速度的曝气效果要比10m/s、30m/s的曝气速度的曝气效果好。

Considering a spherical porous carbon particle immersed in a static ambient atmosphere, the combustion characteristics under three basic conditions: frozen flow, equilibrium flow, partial flow are solved in a half-analytical and half-numerical way. By using the LAEA (Large Activation Energy Asymptotic Method), the departure value of some parameters such as combustion rate, temperature, and concentration are obtained. On this basis, the rules of a carbon particle combustion under various conditions when the gas phase Damk〓hler number is in the range of 0,+∞ are summarized.

建立氧化性环境中相对静止的多孔炭粒燃烧的控制方程，采用半解析、半数值方法求解出炭粒在冻结流、部分流、平衡流三种基本情况下的燃烧规律，并采用大活化能渐近匹配方法，计算出偏离冻结流、偏离平衡流情况下燃烧速率、温度及组分浓度等参数的偏离解，进而总结出炭粒在气相Damk〓hler数为0，∞整个范围内燃烧特性变化规律。

Results indicate:(1) The newly developed simulation technology can form fairly average and easily controllable back pressure downstream the inlet, so it can he used to investigate the back pressure characteristics of hypersonic inlets.(2) By regulating the valve of injection pipe, the simulation technology can realize the switch of hypersonic inlet started state and unstarted state in about 8 milliseconds, so it is suitable to investigate the starting/unstarting/resarting problem of hypersonic inlets.

结果表明：(1)所提出的凹腔喷流技术可在进气道下游形成较为均匀的、可控的背压环境，因此可用于进气道的反压特性研究；(2)适当调节凹腔的喷流总压，并在实验中实时控制阀门的开度，凹腔喷流技术能够在较短的风洞实验时间内（约8s）实现进气道起动、不起动、再起动流态之间的切换，因此可用于进气道的不起动／再起动特性研究。

What's more,the three-dimensional velocity,density and pressure distribution of the flow field in the gravity-fed 3-product H.M.cyclone were studied as well,some conclusions were summarized.

通过对无压给料三产品重介质旋流器流场的三维速度、压强、密度和空气柱的数值模拟研究，对无压给料三产品重介质旋流器内的流场有了更深入和细致的了解，得到了几点有意义的结论。

For example, it may prove difficult to cope with the in-furnace aerodynamic characteristics resulting from the use of a swirl burner on the arch-crown of the W-shaped boiler. In such a case one will not only be deprived of the advantages attributed to the use of the swirl burner but also suffer from a multitude of troublesome issues.

但采用旋流燃烧器后，由于W型锅炉燃烧的特殊性，给锅炉的设计和运行带来了新的情况，如对旋流燃烧器在W型锅炉拱顶采用旋流燃烧器后炉内的空气动力特性不能很好得到掌握，不但得不到旋流燃烧器所带来的优点，还会引起很多问题。

The results of calculations showed that the maximum increments in saltation height and horizontal distance due to the Magnus force were 10.2 and 24.9%, respectively, and that both increments increased with increasing lift-off angle. The maximum increments in saltation height and horizontal distance of sand grains caused by the Saffman force were only 4.6 and 3.7%, respectively. The vertical concentration distribution of Aeolian sand flow follows exponential function distribution whether or not force analysis of saltating sand grains includes Magnus and Saffman force. The effect of Magnus and Saffman force on the vertical concentration distribution of Aeolian sand current makes the rate decrease near sand bed and it is consistent with the effects of Magnus and Saffman force on the saltation height and distance of sand grains.

Magnus力对跃移高度和水平距离产生的最大增量分别可达到10.2%和24.9％，这两个增量均随起跃角度的增加而增大；Saffman力对跃移高度和水平跃移距离产生的最大增量分别为4.6%和3.7%；是否考虑Magnus与Saffman力，风沙流垂向质量百分浓度均服从指数函数分布，Magnus与Saffman力使得风沙流垂向质量百分浓度较不考虑它们的作用呈现出底层的比例较小，上层较大，Magnus与Saffman力对跃移高度的影响基本与其对风沙流垂向质量分布的影响一致，不过Magus力对风沙流垂向质量百分浓度分布影响较大，0-2cm范围内尤为强烈(7.16-10.81)，其他高度层(2-20 cm)的影响相对较小(0-2.95)。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新