动磁式直线冰箱压缩机的设计方法

建立了动磁式压缩机理论数学模型,采用描述函数法对非线性气体力进行了线性化,分析了压缩机系统振动特性.从制冷量和制冷性能系数(COP值)要求出发,提出了一套动磁式直线冰箱压缩机理论设计新方法,从而合理确定压缩机主要结构和性能参数,保证压缩机系统高效运行.样机设计和性能仿真分析表明.此种设计方法是可行的.     

战略驱动 自主创造 精细管理 促进企业持续发展

加西贝拉压缩机有限公司创建于1988年12月,是国内环保、节能、高效冰箱（冷柜）压缩机的专业制造商,国家重点高新技术企业,我国冰箱压缩机行业国家标准修订组长单位。经过20多年的创新发展,公司现有总资产16亿元,员工2400余人,拥有两个制造基地,一个省级技术中心和一个压缩机技术研究所,年产环保、节能、高效冰箱（冷柜）压缩机1000万台以上。近几年来,公司在省、市各级领导的关心支持下,按照科学发展观和“两创”的要求,     

基于VC++和MATLAB混合编程的冰箱压缩机设计软件开发

在深入了解冰箱压缩机内部结构和工作原理的情况下,利用MATLAB提供的引擎技术,实现在Visual C 程序中调用MATLAB,开发出了一套适用于冰箱压缩机的设计软件.     

冰箱压缩机的发展趋势

冰箱压缩机作为冰箱的心脏,其性能的优劣、噪音的高低和质量的好坏是影响冰箱整体性能的重要方面,也是冰箱压缩机研发、设计和生产人员一直关心的问题。随着国内冰箱市场竞争越来越激烈,再加上市场对成本的压力、CFCs替代的国际化要求和冰箱能源效率水平的提出,对冰箱压缩机提出了越来越高的要求。     

冰箱压缩机橡胶垫减振系统设计因素分析

冰箱压缩机的橡胶垫可减小压缩机向冰箱的振动传递,从而降低冰箱的噪音和振动。本文从理论分析、仿真计算、及实验测试几个方研究了冰箱压缩机橡胶垫的关键设计因素。结果表明,橡胶垫的隔振效果和压缩机的质量M,旋转频率f,以及橡胶垫的刚度K和阻尼C有关。从传递力的角度考虑,K越小传递给基础的力越小,但是相对整个冰箱系统而言,存在一个最佳刚度k值使整个冰箱系统的振动和噪音最小。     

一种冰箱压缩机加速寿命试验装置的研制

由于传统的冰箱压缩机试验技术已无法满足当前的需要,在加速寿命理论的基础上,借鉴其它工程领域和科研单位设计的产品加速试验方法,针对冰箱压缩机失效机制和运行特性,介绍一种新型工质冰箱压缩机加速寿命试验台,阐述了试验台系统的组成、工作原理及系统方案设计。     

降低冰箱噪声的试验研究

本文对一种冰箱匹配高效活塞式压缩机后噪声较大的问题进行了研究。这种噪声的峰值频率介于2 0 0～ 315Hz (1/ 3倍频程 )。本文确定了吸气管振动所形成的冰箱蒸发器的振动是产生噪声的根源 ,而吸气管的振动源为机壳的振动和气流脉动 ,并且气流脉动是主要激振力。在上述分析与试验的基础上 ,重新设计压缩机的吸气消音器 ,在吸气管壁钻孔 ,通过这些措施 ,使该冰箱的声功率降低了约 2dB (A) ,提高了冰箱的声质量     

加西贝拉：创新是如何坚持的？

加西贝拉压缩机有限公司是国内高效、环保、节能冰箱压缩机的专业制造商，国家重点高新技术企业，冰箱压缩机行业国家标准制定组长单位。二十多年来，加西贝拉坚持以人为本不动摇，创新发展不停步，严格管理不松懈，以赶超世界先进水平为目标，大力推进观念创新、技术创新、管理创新和营销创新，走出了一条引进消化吸收再创新的发展之路。     

小型制冷压缩机

小型制冷压缩机是小型制冷机的心脏。近几十年来,小型制冷压缩机的结构大约15年左右更换一次。转速也一再增加,产量也逐年增,在第二部分综述了制冷压缩机的主要型式.按电动机安装方式可以分为封闭式、半封闭式和开启式三种;按结构形式来分可以分为活塞式、回转式和螺杆式三种.按制冷剂种类可以分为氟里昂、氨、氯甲烷、二氧化硫几种。在第三部分简要介绍了主要的制冷剂的性能.在第四部分以小型制冷压缩机的典型代表—冰箱压缩机为例介绍了连杆式、滑管式、滚动活塞式三类冰箱压缩机的特点.最后介绍了目前国内外冰箱压缩机的生产情况.     

旋转压缩机在冰箱、空调器上的应用

制冷压缩机是冰箱、空调器制冷系统的心脏,它的性能优劣直接影响到冰箱、空调器的性能。在60年代以前冰箱和空调器普遍使用往复式压缩机(冰箱多采用滑管式压缩机)。60年代开始旋转压缩机在美国研制成功,接着日本亦迅速发展     

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.     

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.……     

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...     

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.     

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.……     

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.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

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.