小型家用混合蓄冷空调系统性能的实验研究

随着家用空调的日益普及，空调耗电量急剧增加。我国开发与推广小型家用蓄冷空调器，其转移尖峰用电负荷的潜力将比在中央空调系统上发展蓄冷空调大得多。小型家用蓄冷空调系统采用外融冰蓄冷，可以明显地节省运行费用；系统采用直接蒸发方式进行蓄冷，可避免冷热转换的中间环节，减少了能耗；相变温度为5～8℃的相变材料利用潜热进行蓄冷，可以改善制冷系统的运行特性。因此研制冰蓄冷与相变材料蓄冷混合的蓄冷空调系统是有意义的。     

Na2SO4.10H2O溶液的特性及其在蓄冷空调技术中的应用

优态盐蓄冷系统具有冰蓄冷和水蓄冷系统的优点，极易与常规空调系统冷水机组连接，是一个非常有应用前途的蓄冷系统。本文讨论了空调蓄冷对相变材料的要求，分析了Ｎａ２ＳＯ４·１０Ｈ２Ｏ的水溶液特性，以及通过添加ＮａＣｌ、ＮＨ４Ｃｌ改变其转熔温度，以满足空调的需要；讨论了此类相变材料蓄冷空调系统的运行方式     

空调蓄冷相变材料的最新研究

相变材料是一种新型的蓄冷材料,5～10℃的相变材料在空调蓄冷系统中的应用越来越受到重视,已成为国际研究的热点。叙述了用于空调蓄冷的相变材料的选择原则和有机、无机相变材料的优缺点,概括和评述了近年来相变蓄冷材料在开发新型材料、提高导热系数和降低过冷度等方面的研究进展,并展望了空调蓄冷相变材料的研究趋势。     

空调蓄冷用相变材料的研究进展

本文综述了空调用相变蓄冷材料的国内外研究进展,简要介绍了相变蓄冷材料的性能要求和基本分类,总结了已有相变蓄冷材料存在的不足,并指出了优化性能的方法,特别是改善无机类材料的过冷、相分离,有机类材料的导热性能差等问题。对比了无机和有机两类材料在相变蓄冷中的优劣,并对今后空调蓄冷用相变材料的发展方向提出了建议。本文侧重强调满足空调蓄冷温区的材料,并针对典型材料展开深入调研和评述,为更好的改善空调蓄冷用相变材料的性能和推动其实际应用提供依据。     

在空调领域应用TBAB载冷的相变蓄冷与潜热输送技术

介绍一种新型的相变潜热载冷剂材料四丁基溴化铵(TBAB)水溶液,以及基于应用此材料的相变蓄冷与潜热输送技术。该项技术可缩减蓄冷空调系统的建设规模,大幅降低空调载冷系统输送能耗,达到节能降耗的目的,值得在空调领域推广应用。     

小型蓄冷空调系统研究

本文阐述小型蓄冷空调系统的工作原理和循环系统，并通过实验分析了相变蓄冷材料的凝固点、融解点、融解热等热学性能。在热性能分析中，用示差扫描量热仪(DSC)来测定蓄冷材料的融解热，用温度测量仪器来测定蓄冷材料的凝固点和融解点，通过热性能分析找到了一种新型蓄冷材料，该蓄冷材料可被应用于小型蓄冷空调系统中。     

空调共晶盐高温相变蓄冷技术的分析

全面介绍与分析了空调共晶盐高温相变蓄冷技术的相变材料的选择、配制、研究方法、材料的札装和蓄冷系统的布置方式与蓄放冷特性，探讨了蓄冷技术研究中需要关注的难点。共晶盐蓄冷技术吸收了水蓄冷、冰蓄冷系统的优点，具有广阔的市场前景。     

一种新型空调蓄冷材料的研制

分析了当前空调蓄冷材料的研究现状及存在的一些问题,提出一种新型的相变蓄冷材料,该材料相变温度适宜,相变潜热大,具有重大的现实意义和实用价值.通过对KCL溶液的相图分析和热力性能的研究,联系实际应用情况,研制出一种新型相变组合材料,其相变温度在-5℃左右,相变潜热为280KJ/Kg.性能稳定,节能效果好,非常适合应用于低温送风与相变蓄冷相结合的空调系统中.     

有机相变蓄冷材料的研究进展

本文概述了有机相变蓄冷材料和有机-无机复合相变蓄冷材料的研究进展,探讨了采用公式指导低共融物相变蓄冷材料配比和提高有机相变材料导热能力的方法,介绍了相变材料在太阳能利用、电力的峰谷平衡、空调节能与冷藏运输等方面的应用研究。指出相变材料的性能特性、相变机理、传热理论模型及复合技术是有机相变蓄冷材料研究的重点内容,有机复合相变蓄冷材料是今后有机相变材料的重点发展方向。     

蓄冷空调新型相变蓄能材料热性能研究

通过实验分析了空调蓄冷材料的凝固点、融点、融解热和相变过程中的热稳定性等热学性能。在热分析中 ,用示差扫描量热仪 (DSC)来测定蓄冷材料的融解热 ,温度传感器用来测定蓄冷材料的凝固点和融解点。通过热分析寻找到了一种新型蓄冷材料 ,其测试结果表明 :该蓄冷材料是蓄冷空调系统中一种高效的蓄冷材料     

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.