气流

The main work and the originality points of this dissertation could be concluded as the following parts:(1) To analyze systematically the mathematical model of LES of air flow in great space, under the case of isothermal and non-isothermal, as well as the combined action of buoyancy and strain. Some basic problems are studied about the LES application into airflow simulation of great space, such as boundary conditions, spatial difference scheme and time advancing scheme, time step etc., which creates the basis for the LES application to indoor airflow simulation.(2) Both the instantaneous and time averaged flow field of great space with multiple jets under isothermal and non-isothermal cases are explored with large eddy simulation method, and also discussed the dynamic characteristics and the law of fluidflow in the great space.(3) Based on the results of LES of the great space and the Fanger thermal comfort indexes, it is brought forward the concept of the series of dynamic thermal comfort evaluating indexes, which could be divided into thermal comfort index with time averaged properties PD, PPD, PMV, thermal comfort index with instantaneous properties IPD, IPPD, IPMV, and time averaged thermal comfort indexes TAPD, TAPPD, TAPMV, and transient situations time averaged thermal comfort indexes TTAPD, TTAPPD, TTAPMV. The differences among them and the calculation methods are discussed, and the four kinds of indexes are calculated with the thermal comfort index PD as an example.(4) Based on the LES results it is discussed the hot air stratification phenomena in air-conditioned buildings in the case with air supply and return registers on the ceiling and the case on the sidewall. The fundamentals of the hot air stratification are studied and the relations of estimating hot air stratification are brought forward.(5) With the advanced apparatus such as hot wire film anemometer IFA300 and laser particle field anemoscope, corresponding model test and site measurements have been done, which are compared with the simulation results and LES is proved a very promising method in air flow simulation indoor.

本文主要工作既创新点体现在以下几个方面：(1)系统分析了等温、非等温和考虑剪切力与浮升力综合作用的高大空间大涡模拟数学模型，并研究了高大空间大涡模拟在室内气流仿真应用中的一些基本问题，如边界条件、空间离散格式和时间推进格式、时间步长选择等问题，为大涡模拟在室内气流计算中的广泛应用打下了基础；(2)首次用大涡模拟方法研究了高雷诺数下高大空间多射流在等温、非等温情况下的瞬时流场和时均流场分布，并探讨了多射流流场的动态特性和流动规律；(3)基于大涡模拟的动态仿真结果和Fanger的热舒适指标，首次系统地提出了动态热舒适评价指标体系的概念：即基于时间平均参数的热舒适指标PD、PPD、PMV；基于瞬时参数的瞬时热指标IPD、IPPD、IPMV；基于时间平均热舒适指标TAPD、TAPPD、TAPMV；以及沿行动迹线的时间平均热舒适指标TTAPD、TTAPPD、TTAPMV，并分析了四类热舒适指标的差异性和计算方法，还以PD值为例对四类指标分别进行了计算；(4)基于数十种工况下空调房间大涡模拟的结果，研究了空调建筑上送上回和侧送侧回两种情况下热分层现象，并探讨了热分层的基本规律，首次提出了避免热分层现象的判断公式；(5)在暖通空调领域，首次使用IFA300热线风速仪、激光粒子速度场仪等先进设备，完成了与大涡模拟相对应的模型试验，并把实测结果与仿真结果进行了对比，说明LES在室内气流仿真方面是一种很有前景的方法。

The air flow excitation force of leaf peak clearance evocable by impeller eccentricity is the important part of the air flow excitation force, so the research of it is very important too.

而由叶轮偏心引起的叶顶间隙气流激振是气流激振的一个重要方面，因此，加强透平机械中由叶轮偏心引起的叶顶间隙气流激振的研究也显得非常重要。

The theories on pyrolysis and coking and hydrogenation of heavy oil are used to know the liquefaction and gasify and coking of coal. 3. The results of particle feeding in the hot plasma jet (1) By using the cold state of spraying the diesel oil mist transversely in the air flow at the subsonic and ultrasonic speed to imitate the stress condition and motion trace of coal powder in the plasma jet, it shows that with the speed of air flow changed from subsonic speed to ultrasonic speed, the uniformity of mixture between the coal powder with certain speed and air flow becomes worse, mixture length becomes shorter, which agrees with the law of momentum transfer.

三、热等离子体射流中颗粒注入研究的结果(1)利用柴油油雾在亚、超音速气流中横向喷射冷态模拟煤粉在等离子体射流中的受力和运动轨迹，结果表明随着气流速度由亚音速向超音速增加，一定速度的煤粉与气流混合均匀度变差，混和长度增加，符合动量传递规律。

When an air jet is allowed to expand freely, the moving air is contained within an imaginary cone whose axis is coincident with that of the air jet.

当一股气流自由膨胀时，运动着的气流构成一个假想的圆锥体，其轴线与气流的轴线相重合。

The test results show that the performance of ISD will improve with the increase of air temperature, mass flow of air and initial moisture content of wood particles and the decrease of air humidity and mass flow rates ratio.

研究结果表明，随着气流温度的升高、气流湿度的下降、气流流量的增加、刨花初含水率的提高及载带率的减小，刨花对撞流干燥的强度也随着提高。

Using FLUENT, a large-scale fluid project emulation software, a numerical simulation for cleaning air flow field were made, the intact equivalence line chart and vector graph of the air flow speed distribution were obtained, which provide more overall understanding to the cleaning air flow field speed distribution.

利用大型流体工程仿真软件FLUENT，对清选气流场进行了数值模拟，获得了完整的清选气流速度分布的等值线图和矢量图，对清选气流场的分布有了更全面的了解。

The results showed that: 1 during drying, the heat transferred between process gas and cut tobacco before feeding point in HXD could be scaled by ', which is the reciprocal of temperature difference of process gas...

结果表明：①在干燥过程中，HXD喂料点前工艺气流与烟丝间的换热量可用干燥前后工艺气流温差的倒数来衡量；②在其它控制参数不变，只改变排潮模式的情况下，设置为手动控制排潮时，干燥过程的换热量总是较低；③当设置为自动排潮且HXD蒸气注入量超过1800kg/h时，工艺气流的干燥能力随着注入量的增大而降低。

An the orthogonal test of mist eliminator is conducted, and it is found that the angle of corrugated baffle and Reynold number of gas have a great influence on both the separation efficiency and the pressure drop of mist eliminator.

首先对除雾器除雾性能进行正交试验，并采用直观分析法和方差分析法对正交试验结果进行了分析，发现波形板曲折角α对除雾效率η影响显著，对压降影响特别显著，α为45°时，除雾器除雾效率高且压降适中；斜边长与板间距比值L/b对除雾效率η有一定影响，但对气流压降影响不大；气流雷诺数Re对除雾效率η和气流压降影响显著。

Result of computation of content of the oxygen in ignition air current makes clear, the aerobic content in air current of microwave sirocco ignition is 21%, content of the oxygen in gas ignition air current is 8.59%.

点火气流中氧气含量计算结果表明，微波热风点火气流中的氧气含量为21%，煤气点火气流中氧气含量为8.59%。

From the results, it is found that,(1) decreasing the angle between the air slot and the spinneret axis both the air velocity in the direction of the spinneret axis and the air temperature will be increased.

测试和模拟结果表示：(1)气流流道与喷丝孔轴线的夹角越小，喷丝孔轴线方向的气流速度越大，气流温度越高，但受结构设计的限制。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。