新型太阳能冷管吸附制冷的实验研究

根据固体吸附式制冷原理,利用太阳光作为热源,对一种新型太阳能冷管的制冷性能进行试验研究。该冷管冷凝器采用薄壁不锈钢材料,利用沸石分子筛—水作为吸附工质对。实验结果表明:在太阳辐射强度为21.01~22.90MJ/m2,室外环境温度最高为31℃时,该太阳能冷管的单支制冷量大约为145k J,制冷温度为11℃,制冷系数约为0.118。     

船用轮机尾气余热吸附式冷管的实验研究

船用轮机尾气余热吸附式冷管实验以船舶轮机余热利用为背景,基于吸附制冷原理,在一支密闭管内通过吸、脱附循环获得冷量的吸附式制冷单元管;该冷管采用13X沸石分子筛-水工质对,在脱附温度为200℃,吸附温度为12℃工况下,蒸发温度达到了3℃,获得了198.8KJ制冷量,有效地实现了轮机尾气余热的再利用,是一种对环境友好、没有温室效应和臭氧破坏势的制冷方式,该研究具有潜在的应用价值,具有环保和节能的特点。     

吸附制冷用吸附剂性能测试及实验研究

研究吸附工质对的性能对于吸附式干燥、除湿、制冷具有重要作用,而吸附剂的吸附量、导热系数和吸附材料的性质、温度、压力等许多因素有关,因此用实验来测定就变得十分的有必要。本文以3A作为吸附剂,水作为制冷剂,组成吸附式制冷工质对,通过液位法对工质对的吸附制冷性能进行了研究。结果表明:它的最大吸附量为24.5g,最大吸附率为0.112g/g。本实验吸附床中3A沸石分子筛的量为218.5g,在脱附温度为260℃,吸附环境温度为25℃时,根据已有的对太阳能冷管的改进实验,选用同样材料的太阳能冷管计算时,可得其制冷量为147.864J,制冷系数COP为0.116。     

沸石吸附式制冷技术的研究进展

综述了国内外沸石分子筛吸附式制冷技术的研究进展,主要包括沸石分子筛制冷的特性、研究现状及存在问题,并介绍了今后的研究重点和方向。     

太阳能固体吸附式制冷的应用与发展

本文在综合前人研究成果的基础上,分析了太阳能固体吸附式制冷的特点,简述了太阳能吸附式制冷的发展现状,并介绍了其基本原理和两种循环类型,及太阳能集热器的一些情况。对硅胶—水,沸石分子筛—水为吸附工质对的系统进行了理想循环计算,发现前者比后者更适合于太阳能吸附制冷系统,提出了新的观点。     

沸石分子筛吸附式制冷 Ⅰ.沸石分子筛体系的选择

用高真空吸附重量法测定了水和乙醇在 NaY、13X、5A 等沸石分子筛上的吸附等温线,吸附温度范围从25℃到300℃。阐述了沸石分子筛用于吸附式制冷的吸附理论基础,根据液-气-沸石的稳态平衡方程对液体-沸石吸附体系制冷的物理化学性质进行了描述。按照不同用途的制冷要求对吸附体系进行了选择。发现乙醇液体-沸石体系(如乙醇-5A 体系)可用于小循环量的低温制冷如制冰、冷冻机等,而水-沸石体系(如水-NaY 体系)可用于大循环量的制冷如空调、冰箱等。     

沸石分子筛吸附式制冷 Ⅱ吸附式制冷的循环系统

利用自制的沸石分子筛,在自行设计的吸附式制冷模拟装置上,对吸附剂5A、NaY、CaY、13X及CaX等沸石分子筛和制冷剂水系统进行了制冷效果的测定;讨论了吸附速度、脱附温度对制冷效果的影响;通过吸附等温线的测定,计算了制冷循环系统中水的循环量,并测得分子筛再生时开始脱附的温度Ts值和再生后开始吸附的温度Ts’值。实验结果表明每公斤所研究的分子筛在单级吸附—解吸循环系统中能够产生制冷量为62—100千卡(Tev=0℃,Tcond=Tads=14.5℃,Treg=120℃)。     

一种新型吸附性制冷吸附剂的性能研究

吸附剂在吸附式制冷中起着至关重要的作用,13X沸石分子筛作为物理吸附剂具有稳定和安全的特点。本文通过闭式吸附测试系统对分别浸泡5%,10%,15%,20%CaCl_2溶液的13X沸石分子筛进行吸附性能测试,得出通过浸泡一定浓度的CaCl_2溶液可以提高13X沸石分子筛的吸附能力,但是一旦超过临界浓度,浸泡高浓度CaCl_2溶液会减弱13X沸石分子筛的吸附能力。     

ZSM-5沸石在空调应用中的吸附脱附性能研究

针对固体吸附式制冷在空调领域的应用,建立了一套采用ZSM-5沸石-水作为吸附工质对的实验研究系统,对其吸附脱附性能进行了实验研究,得到了吸附脱附性能曲线。比较了不同吸附床温度以及吸附床有无保温情况下,ZSM-5沸石分子筛对水的吸附情况:低温情况对水蒸气的吸附量随吸附时间明显增加,但吸附率逐渐变慢;床温升高,吸附剂达到吸附平衡所需时间缩短,平衡吸附量则有所降低。     

低温驱动沸石-水吸附式制冷机的性能研究

本文研究的合成沸石-水吸附式制冷机采用FAMZ01沸石作为吸附剂,吸附床选择翅片涂抹式吸附床,通过实验研究该制冷机的制冷功率、制冷性能系数(COP)随热源温度、冷冻水进口温度的变化规律。结果表明,该吸附式制冷机在55℃的热源下就可以稳定输出制冷量,并在驱动热源为65℃左右展现其较佳的性能。     

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.……     

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.……     

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.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.