与冰蓄冷相结合的大温差风机盘管系统性能研究

介绍了与冰蓄冷相结合的大温差风机盘管系统原理,并在冰蓄冷空调系统的不同运行工况下,对风机盘管的能效比和冷风比的理论计算值和实际运行值进行了比较,分析了冰蓄冷和大温差风机盘管相结合情况下的能效。     

河水供冷中央空调风机盘管的干工况设计与运行分析

基于对全国首例河水自然冷源中央空调系统的案例研究，对该中央空调系统风机盘管的设计与技术创新过程及运行效果进行了理论分析和实践总结，利用盘管冷量换算方程对其风机盘管进行了制冷量估算，并建议自然冷源空调系统的风机盘管应按干工况设计。     

北京市某大厦通风空调设计

介绍了北京市新疆大厦通风及空调系统的设计。该工程采用了冰蓄冷和末端低温送风的方案,空调水路采用二次泵变频方式,根据建筑功能分区分别采用可变新风比的一次回风全空气系统、风机盘管加新风系统。     

国产风机盘管选型中存在的问题及解决办法

就目前的风机盘管空调系统的特点,对国产风机盘管选型中存在的问题进行了分析,并提出相应的解决办法.     

风机盘管系统在地铁空调中的应用

介绍了风机盘管系统在地铁类建筑中的具体应用形式;以天津某地铁站为例,分析了风机盘管系统应用的可行性和经济性,以期为风机盘管系统在地铁类建筑中的应用提供参考。     

风机盘管变冷水温度运行的性能研究

通过实验分析影响风机盘管冷量的因素，研究了在风机盘管空调系统中冷水温度变化对末端空气处理设备热湿处理能力的影响；确定了判断满足风机盘管设计要求的变水温工况方法及最大冷水供水温度，为风机盘管空调系统变水温节能运行提供依据。     

浅谈风机盘管加新风空调系统噪声控制措施

本文针对风机盘管系统噪声问题，通过对多个风机盘管加新风空调系统的设计和安装特点的分析，总结了控制该系统噪声较为有效的措施。     

贮冰槽的性能测试与分析

本文介绍了５０ＲＴＨ盘管式冰蓄冷空调系统，并对贮冰槽性能进行了测试与分析，得出了充冷与释冰特性及其他技术指标     

风机盘管选型方法的比较

分析空调系统中常用风机盘管的类型、特性,对工程设计中常见的选型方法进行分析和比较,指出风机盘管的选型应综合考虑冷负荷、风量,并要注重经济性、舒适性。     

BIM+测量机器人技术在风机盘管安装质量控制中的应用

本文以中科D-6项目机电安装工程风机盘管水系统施工为例，结合项目施工的风机盘管安装质量控制情况统计了风机盘管安装的合格率，共检查28处，合格率为78%，并对收集的50条影响风机盘管水系统安装质量的问题信息进行详细分析整理，得出主要原因是技术交底不够详细；施工人员对风机盘管安装方式方法掌握不熟练；测量设备不足等。项目团队通过BIM+测量机器人技术在风机盘管水系统安装质量控制方面的应用，风机盘管水系统安装质量验收总体合格率达93.4%，且大大提高了施工效率，为后续同类工程的施工提供一定的参考。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.