导叶式旋风管排气管内流动减阻的试验研究

通过对导叶式旋风管内流动参数的测量分析,发现排气管内气流旋转强度高,并存在“滞流”、“倒流”及逆压梯度等无益于颗粒分离的流动状态,造成排气管内压力损失约占旋风管总压降的22%。在排气管内安装框形结构后,可有效削弱和抑制上述耗能流动,在保证分离效率基本不变的前提下,使旋风管减阻幅度达到9%。     

物质流、能量流与信息流协同的探讨及应用

根据反映生产设备与环节特性的数学模型及能量与生产管理信息系统，对物质流、能量流与信息流的协同进行了探讨，并针对一个一般的工业企业建立了其数学模型。通过实际系统与仿真系统结合形成闭环的信息结构，在每个时间周期根据该时刻的信息流（已知的与预测的）对物质流、能量流进行最优协调，该方法能有助于企业合理使用能量与最优安排生产。     

Field synergy principle of heat and mass transfer

Simultaneous heat and mass transfer widely exists in nature and engineering, and it is of vital importance to enhance heat and mass transfer efficiency. In this paper, field synergy equation of heat and mass transfer is derived from its energy equation. Results show that the total transferred heat （including the conducted heat and the heat transferred by mass diffusion through the heat transfer interface） is determined by the values of fluid velocity and enthalpy gradient as well as the value of synergy angle α of velocity vector and enthalpy gradient field. Decreasing the value of α enhances the heat and mass transfer. This means the higher the synergy of velocity vector and enthalpy gradient field, the higher the total transferred heat. By the synergy principle of heat and mass transfer, some methods may be developed to improve the heat and mass transfer efficiency.     

场协同下板翅式换热器效率的研究

在对板翅式换热器的传热与流动进行分析的基础上,对Prasad的模型进行了改进,通过数值计算得到了温度场分布.在错流情况下与试验结果进行了比较,二者比较相符.利用场协同原理,研究了不同的流道布置下板翅式换热器的温差均匀性因子,结果表明:不同的流体组织结构的变化,使得换热器的速度场和温差场的协同性不同,直接带来温差均匀性因子不同,从而导致换热器的换热性能的改善或恶化.     

低雷诺数下附属棱柱的圆柱绕流减阻

目前圆柱绕流减阻方案的探索一直是绕流研究的热点,有关棱柱作为扰流柱对圆柱减阻效率影响的研究却较少.基于不可压缩黏性流动Navier-Stokes控制方程,利用OpenFOAM对附属棱柱下圆柱绕流问题进行数值模拟.在圆柱上游或下游设置双扰流棱柱,研究了雷诺数为200时不同角度、间距比的棱柱对其升力、阻力系数和涡脱频率的影...     

Plate drag reduction with low surface energy coating in water tunnel

Conclusion The drag of the flat plate model showed that the low surface energy coating models were capable of reducing drag (18%–30%) in a certain range of speed. For a solid with a low surface energy that has low tensile strength, the effect of surface characteristics on the turbulent structure is measured and a significant difference between Al plate and plate covered coating of low surface energy is found. The tensile slrength of the bond between water and solid material is the predominant parameter.     

离心力场作用下对流换热场协同理论的实验验证

对离心流化床(CFB)干燥器中气体与被干燥颗粒物料之间的强制对流换热进行了实验研究．实验结果表明，在一定转速范围内，当气流速度方向和热流方向(即温度梯度方向)一致时，离心力场作用下气体流过颗粒层的对流换热准则关联式与由场协同理论中推导的结果具有同样形式，从而验证了场协同原理的正确性．     

不同倾斜角新型板式换热器特性及场协同原理分析

通过三维CFD数值模拟软件ANSYS-CFX模拟分析一种新型波纹板式换热器——复合人字形板式换热器,分析其倾斜角β为20°～70°的传热和阻力特性,并对不同倾斜角的复合人字形板片进行场协同理论分析。数值计算结果表明:在β=60°时复合人字形板式换热器比普通人字形板式换热器的摩擦阻力系数低8%左右,综合性能提高25%左右;β=20°时速度场、温度场和压力场协同最好。     

仿生表面微结构减阻优化及机理研究综述

介绍了自然界中几种较为典型的非光滑结构表面生物,阐明了合理表面微结构可以改变近壁区湍流结构的规律,针对表面微结构的类型、减阻研究实例、减阻机理和减阻应用等4个方面进行了评述,提出了沟槽扩展类型,并指出减阻机理研究应拓展至复杂形态结构。分析表明:微结构类型对减阻效果有较大影响,减阻优化及其机理研究是仿生表面微结构减阻工作的重点,仿生表面微结构减阻优化可进一步提高节能降耗的效率,在飞行器、高速列车、汽车等工程领域具有广泛的应用前景。     

场协同原理强化管外降膜吸收传热特性实验研究

对基于场协同原理设计的两种强化传热管型进行了LiBr降膜吸收水蒸气过程的传热实验研究,并与光滑铜管作比较,考查该传热管型在吸收过程中的强化作用.实验测量参数包括;溶液进出口温度、浓度,流量,冷却水进出口温度、流量等.实验结果表明,两种强化传热管型在低雷诺数时对LiBr降膜吸收传热的强化比分别为20%和50%,而且随着雷诺数的增大而增大.利用场协同理论和降液膜流动的波动特性分析了强化降膜吸收过程传热特性的物理机制,发现速度矢量与温度梯度的夹角及降液膜厚度形成的阻力对对流换热有一定影响.     

基于动能密度时间变化率的固/液流动分离判据

在空间场中动能密度的时间变化率有许多极小值,定义流动分离发生在其最小值处．可利用流体的无粘流动解计算动能密度值,而采用保角变换的方法,则可获得复杂几何形状下的有势流场解,从而很容易确定出可能的流动分离位置．将此判据应用于流线外型的设计,对延迟流动分离及减少阻力是有帮助的．对于均匀来流的圆柱绕流问题,该判据预示流动分离发生在离后驻点角度为±５４．７４°处,而已知的实验数据指出：流动分离发生在±５０°与±５８°之间．对于长轴∶短轴＝１∶６的椭圆翼剖面,当来流攻角在７°与８°之间时,将开始发生严重的失速现象．英国皇家空军３４翼剖面具有相同的长短轴比）的实验数据表明,失速开始发生在１２°与１４°攻角之间,可见理论值与实验值接近．文中讨论了其它形状的翼剖面,说明如何通过选择机翼的形状来延迟失速现象的发生．     

新型强化传热螺杆结构传热性能数值研究及场协同分析

利用CFD软件fluent对普通螺杆结构和新型强化传热螺杆结构在塑化计量段中的三维非等温流场进行数值模拟,研究两种结构流道内熔体的速度场、轴向和径向温度场、对流传热系数及场协同角的不同。结果表明：在塑化过程中,新型强化传热结构存在着径向的对流传质过程,加强了径向的对流传热,因此有较好的径向温度分布;新型结构较普通螺杆结构有较高的对流换热系数和较好的场协同性,从而加强了螺杆的对流传热。     

镍铁生产过程节能减排技术应用研究

针对镍铁企业节能减排技术进行了研究,计算了镍铁生产中的物质流和能量流.根据计算结果进行节能减排关键环节识别,并对节能减排技术进行筛选和评估,提出镍铁生产节能减排技术方案.     

Physical quantity synergy in laminar flow field of convective heat transfer and analysis of heat transfer enhancement

Based on the principle of field synergy for heat transfer enhancement, the concept of physical quantity synergy in the laminar flow field is proposed in the present study according to the physical mechanism of convective heat transfer between fluid and tube wall. The synergy regulation among physical quantities of fluid particle is revealed by establishing formulas reflecting the relation between synergy angles and heat transfer enhancement. The physical nature of enhancing heat transfer and reducing flow resistance, which is directly associated with synergy angles α,β,γ,φ,θ and ψ; is also explained. Besides, the principle of synergy among physical quantities is numerically verified by the calculation of heat transfer and flow in a thin cylinder-interpolated tube, which may guide the optimum design for better heat transfer unit and high-efficiency heat exchanger.     

Physical quantity synergy in the field of turbulent heat transfer and its analysis for heat transfer enhancement

Based on the principle of physical quantity synergy in the field of laminar heat transfer, and according to the models of zero equation and k-ε two equations for the turbulent flow, the synergy equations for both energy and momentum conservation in the turbulent heat transfer are established. The synergy regulation among heat flux, mass flow and fluid driving force, and the mechanism of heat transfer enhancement it reflects are revealed. The synergy principle of physical quantity in the thermal flow field is extended from laminar flow to turbulent flow. The principle is verified to be universal by the calculation of heat transfer enhancement in a tube with an insert of helical twisted tape. Thus, corresponding to the synergy relation among physical quantities in the turbulent flow field, the performance of convective heat transfer and flow resistance for the tubes with different heat transfer components and surface can be compared through theoretical and computational analysis, which thereby provides a guidance for designing heat transfer units and heat exchangers.     

最小耗能原理及其在塑性力学中的应用

在经典塑性力学中,屈服准则、本构关系都是通过观察实验结果而提出的假设.塑性力学中的变分原理也是类比于弹性力学中的变分原理建立的.介绍一个具有新内涵的最小耗能原理以及用它解决问题的三种途径,通过这三种不同的途径分别导出了塑性力学中的Mises屈服准则、各种增量型的塑性本构关系以及可以作为建立各类力学(包括塑性力学)变分原理统一理论框架的最小功耗原理,从而证明了这个具有新内涵的最小耗能原理可以在塑性力学中发挥重要的作用.     

Ellingham图及其在金属制取中的应用

说明了金属氧化物热力学稳定性与其生成反应的标准自由能变化之间的关系，分析了Ｅｌｌｉｎｇｈａｍ图的热力学意义，讨论了金属还原反应的自发性，说明了选择不同金属氧化物的还原剂的热力学依据。     

The extremum principle of mass entransy dissipation and its application to decontamination ventilation designs in space station cabins

In terms of the analogy between mass and heat transfer phenomena, a new physical quantity, i.e. mass entransy, is introduced to represent the ability of an object for transferring mass to outside. Meanwhile, the mass entransy dissipation occurs during mass transfer processes as an alternative to measure the mass transfer irreversibility. Then the concepts of mass entransy and its dissipation are used to develop the extremum principle of mass entransy dissipation and the corresponding method for convective mass transfer optimization, based on which an Euler＇s equation has been deduced as the optimization equation for the fluid flow to obtain the best convective mass transfer performance with some specific constraints. As an example, the ventilation process for removing gaseous pollutants in a space station cabin with a uniform air supply system has been optimized to reduce the energy consumption of the ventilation system and decrease the contaminant concentration in the cabin. By solving the optimization equation, an optimal air velocity distribution with the best decontamination performance for a given viscous dissipation is firstly obtained. With the guide of this optimal velocity field, a suitable concentrated air supply system with appropriate air inlet position and width has been designed to replace the uniform air supply system, which leads to the averaged and the maximum contaminant concentrations in the cabin been decreased by 75% and 60%, respectively, and the contaminant concentration near the contaminant source surface been decreased by 50%, while the viscous dissipation been reduced by 30% simultaneously.     

变离心力场中等截面冷却通道的流量计算和实验研究

本文用数值计算得到的数据集，回归出在变离心力场下，等截面管流由于热阻力引起的变密度流流量减少公式，并用热平衡法在旋转试验台上测量了加热条件下通道内的加热量和平均流速．由实验数据集回归出的流量减少公式与数值计算结果相符．     

大系统中物质流、能量流与信息流的基本特征

把大系统中物质、能量和信息的流动综合起来考虑,引入势和阻的概念来分析大系统中物质流、能量流和信息流在流动过程中的基本特征,并从协同学和熵的角度给出了物质流、能量流和信息流子系统的协同结构,使各个子系统相互协调、配合、制约、促进,从而形成3个子系统在时间尺度和空间尺度上的有序结构,最终使得由其组成的大系统达到全局最优,对大系统的综合优化、节能减排、降低物流成本、提高用能效率有指导意义.