雷诺数

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。

In order to study the stability of non-Newtonian fluid and its flow pattern discrimination method,the integral stability theory and local stability theory are applied to the concentric annulus flowing of plastic fluid and power-law fluid,then a relevant stability parameter expression of discriminating flow pattern is derived and set up in the paper.

针对非牛顿流体的稳定性问题及其流态判别的研究，将整体稳定性理论及局部稳定性理论应用于塑性流体和幂律流体在同心环空的流动中，建立和推导出相对应的判别流动状态的稳定性参数表达式。这些参数的临界值与牛顿液体流态准数雷诺数的临界值，同样具有与液体流变性无关的特点。

And the influence factors such as suspension concentration,operating pressure,Reynolds number and Euler number were established.

结果表明，死端过滤速率衰减模型中过滤速率与时间呈幂函数关系、而十字流过滤速率衰减模型中过滤速率与时间则呈一次函数关系，死端过滤时悬浮液浓度和气压过滤压力对其过滤速率衰减模型系数的影响均呈三次函数关系，在十字流过滤时悬浮液浓度、操作压力以及雷诺数对模型系数b的影响均呈线性关系，轴向流十字流过滤速率衰减模型系数b与欧拉数呈反比，而旋转流十字流过滤时则模型系数a与欧拉数呈反比关系。

Dimensionless equation of air flow resistance is functional relation of Euler number, Reynolds number and Prandtl number, is set up after experimental data is analyzed Air resistance through cooling coil is conveniently computed , fan of the new cooling tower is correctly selected and suitable distance of among cooling tubes is designed by the dimensionless equation.

建立了空气流动阻力的准则方程，即欧拉数Eu与雷诺数Re、普朗特数Pr之间的函数关系。利用这个准则方程可以方便地计算空气流经冷却盘管的阻力，合理地选配封闭式冷却塔所用风机和设计冷却盘管的管间距。

Firstly, the two parts are solved separately, and the results are then coupled together. Because the thickness of the combustion reaction zone at high Re and Da numbers is less than the turbulent diffusion scale in diesel engines, the flame is extremely thin, its micro-structure keeps the laminar structure, so the turbulent flame can be regard as the ensemble of locally one dimensional, thin laminar flamelet embedded within the turbulent flow field.

由于柴油机中在高雷诺数和高Damkoeler数的情况下，燃烧反应区厚度小于湍流耗散尺度，火焰极薄，其微元保持层流结构，因此，湍流火焰可视为嵌入湍流流场内局部具有一维结构的薄的层流小火焰的系综，这便构成了层流小火焰模型主导思想，同时也使层流小火焰模型模拟柴油机湍流燃烧过程成为可能。

The analytical results showed that Reynolds number and Mach number have a rather obvious effect on airfoil aerodynamic performances.

分析结果表明：雷诺数和马赫数对翼型气动性能有较大的影响。

The reasonable value ranges of turbulent Prandtl number for different Reynold numbers were suggested. The conclusions are valuable for the study of various complicated flows using mathematical models.

得出了紊动普朗特数在大小不同雷诺数下的合理取值变化范围，其结论对采用数学模型研究各种复杂流动具有指导意义。

Experimental results indicate that the B/A value greatly affects the internal Nusselt number and friction factor of the twisted tube because the parameters decrease with the increase of B/A and S/d values, more rapidly with the former, and that the Nusselt number and friction factor of the twisted oblate tube increase respectively by 30%~150% and 20%~50%, as compared with those of the smooth tube at the same Reynolds number and Prandtl number.

实验结果表明：高扭曲比螺旋扁管的管内努塞尔数和阻力系数均随B/A值和S/d值的增大而减小，但随B/A值的增加而减小得更快，B/A值对高扭曲比螺旋扁管的管内传热与流阻性能影响更大；在相同雷诺数和普朗特数下，高扭曲比螺旋扁管管内的努塞尔数为光滑管的1.3~2.5倍；阻力系数为光滑管的1.2~1.5倍。

An advanced combined turbulent lubrication model is proposed: low turbulence Reynolds number k-e model is used to describe the flow in the near-wall regions, and algebraic Reynolds stress model is used to describe the flow in the turbulence kernel, with flow continuity kept between the two models and transition criterion set to fit Leutheusser's measurements.

提出了先进的复合型紊流润滑理论：以低紊流雷诺数k-e模式描述近壁区内的流场，而以代数雷诺应力模式描述紊流核心区内的流场，二区间流场连续过渡，并依据Leutheusser实验结果设定过渡准则。

Using tools from dynamical system theory, such as phase space diagrams, Frequency analysis, Poincare sections and the calculation of statistical quantity of chaos: the correlation dimension, Reni entropy, Laypunov exponent and so on, the different solutions to the Navier-Stokes equations at different values of the Reynolds number have been identified and characterized through reconstructing the phase space of velocity time series by means of time delay and dimension embeding.

通过时间延迟和维数的嵌入对速度时间序列重构相空间，利用非线性动力系统理论方法诸如相空间分析，频谱分析，Poincare映射，以及通过对混沌统计量：关联维数，Reni熵，Laypunov指数等计算，对不同雷诺数N-S方程解的特征作了分辨。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。