小管径平行流冷凝器在小功率空调上应用研究

通过数值模拟设计出与2排φ5管翅式冷凝器性能相当的12mm小管径平行流冷凝器,并制作样品,进行整机性能测试。实验结果与模拟结果对比,能力误差控制在3%以内,制冷剂侧压降误差小于15%,符合工程设计精度,与φ5管翅式冷凝器整机性能对比,12mm宽扁管平行流冷凝器重量减少了1.5kg,冷媒充注量减少了20～25%,能力提高了0.5%,能效提高3%,且成本有所降低,该方案拓宽了平行流冷凝器应用范围,可在2匹以下家用空调中推广。     

8 mm扁管平行流冷凝器在家用空调上应用研究

通过数值模拟设计出与2排φ5管翅式冷凝器性能相当的8 mm扁管平行流冷凝器,并制作样品,进行整机性能测试。实验结果与模拟结果对比,能力误差控制在3%以内,符合工程设计精度,与φ5管翅式冷凝器整机性能对比,8 mm扁管平行流冷凝器重量减少了50%,冷媒充注量减少了30%,能力能效相当,且成本有所降低,该方案拓宽了平行流冷凝器应用范围,可在家用空调中推广。     

平行流冷凝器管内强化传热模拟分析及试验研究

基于管内侧强化换热技术理论,从换热设备小型化角度出发,设计出一种新型齿槽扁管平行流冷凝器。其数值模拟结果与实验结果对比:换热量误差控制在3%以内,制冷剂侧压降误差小于15%,符合工程设计精度;且与传统的光滑扁管平行流冷凝器在空调整机性能试验对比:新型齿槽扁管平行流冷凝器重量减轻了40%,空调整机能效提高0.5%,成本降低15%。     

平行流冷凝器在家用空调上的实验研究

为了推广平行流冷凝器在家用空调器中的应用,本文根据换热器相关理论,结合实验,研究平行流冷凝器中扁管规格、翅片参数以及不同流路布置对空调性能的影响。提出了家用空调用SF行流冷凝器优化性能的措施,为今后开发平行流式冷凝器空调提供了参考。     

平行流换热器在空调器柜机中应用的实验研究

平行流换热器具有体积尺寸小、换热系数高、系统制冷剂充注量少等优点,在房间空调器中有较大的应用前景.设计了应用于5hp柜机的平行流室内换热器,通过实验测试,对比分析了室内机采用平行流换热器与普通管翅式换热器的空调器性能,并对平行流换热器空调器的制热性能进行了优化.结果 证明:相对于普通管翅式换热器的柜机,采用平行流换热器时,其制冷量提高了10.2％,但制热量衰减了5.7％;在系统中增设闪蒸器后,其制热性能比采用管翅式换热器时略有提升.     

空调器三种冷凝器的性能对比

探讨以外径为φ7mm或φ9mm的铜管做基管,配以三种不同宽度尺寸的铝箔为外肋片的冷凝器,即三种规格型号的冷凝器:21.65mm铝箔对应φ9mm铜管,12.7mm或18.19mm铝箔对应φ7mm铜管,将它们分别装入在同一系统(蒸发器和压缩机相同)中,通过试验比较它们的性能。根据实验和数据的结果,总体上φ7mm的冷凝器较φ9mm的制冷性能更优,并且成本更低。     

5mm管空调冷凝器翅片的优化设计

为了提高5mm管冷凝器的空气侧换热性能,建立了5mm管冷凝器翅片的优化设计方法。通过依次优化翅片的高宽比、翅片大小、开缝形式和结构,提出了优化后的翅片结构,并通过实验验证了优化后翅片性能的实际提升效果。研究结果表明,优化后5mm管翅片的实际换热性能提升了3.6%,空气侧实际压降增加了1.4%,提高了5mm管空调冷凝器的性能。     

微通道换热器新型扁管的热力学性能评价

微通道换热器由于采用铝合金扁管,其防腐特性需要强化。现有技术手段主要通过在挤压扁管表面喷覆含锌层,钎焊后在扁管厚度方向形成电位梯度来实现电化学防腐机制。然而实际应用中发现该方法在家用空调的恶劣运行环境下效果欠佳,且极易造成管翅分离而导致性能衰减。近几年,汽车空调行业出现一种用于平行流冷凝器和蒸发器的多孔折叠扁管,具备更好的防腐特性,本文对该种扁管进行了换热性能的研究,以论证其在家用空调行业中应用的可能性。     

微通道冷凝器性能研究及影响因素分析

本文通过数值模拟的方法,对一种用于热泵热水器的微通道冷凝器的传热流动性能进行研究,并分析了翅片间距,传热温差及扁管厚度对冷凝器性能的影响。结果表明,相对于外绕铜管冷凝器,微通道冷凝器传热性能有较大提高,增大温差能明显提高其传热性能,而翅片间距和扁管厚度对传热性能影响不大。     

Φ5冷凝器对空调性能影响的分析及其应用

本文从降低企业的生产成本角度出发,通过试验分析对比,Ф5冷凝器的换热性能较好,制冷量提高了4.4%,能效比提高了2.28%,可以在空调器上使用Ф5冷凝器替代Ф7冷凝器.     

干式变压器企业的领跑者--访山东省金曼克电气集团股份有限公司

在我国改革开放和经济建设中,随着民营企业的崛起,外资企业的抢滩,加之近几年变压器制造所需冷轧取向硅钢片、铜等主要原材料的价格爆涨,变压器行业竞争异常激烈。民企分得低端市场份额,外企垄断了高端市场,国营企业的市场份额在逐年递减,甚至一些曾颇为风光的老字号国企早已销     

当美食遇上小家电

俗话说“民以食为天”，一点不错，当美食摆在我们的面前，任何完美的减肥计划都会半途而废，实现苗条身材的宏伟目标也早被抛到九霄云外，这就是美食的号召力！     

Trickle impregnation of small motors

Trickle impregnation is a method of coating the windings of armature and stator components with a solventless polyester or epoxy resin. The process involves preheating the windings, dispensing a measured amount of resin, and heat-curing the resin. The advantages of trickle impregnation are presented and the materials used (polyesters and epoxies) are detailed. Three machine configurations that have been designed to perform the trickle impregnating operations of heating cores and dispensing resin and described: dial type, flow-through ovens, single-station machines, and batch-process machines. Special considerations relating to resin dispensing are also discussed     

脉冲电流测量小电阻

提出了一种新的精确测量小电阻的方法。通过介绍用脉冲电流测量小电阻的优点,引出了脉冲法测量电阻的装置的硬件和软件设计,并分析了该装置的性能。     

分布式小电流监测系统

基于对电力系统小电流单相接地故障的分析，采用了以单片机为核心，利用先进的现场总线原理，以工业控制计算机为平台组成分布式小电流监测系统，实现对小电流接地故障的实时监测和分析。     

Power quality of small rural industries

Successful and economical operation of small rural industries (e.g. grain, dairy, irrigation, pig, poultry, beef feedlots, etc.) is a fundamental objective of society. However, when the performance and life expectancy of industrial electronic and electrical equipment is significantly affected by power supply anomalies caused by polluting loads at an industrial site and by utility normal operational activities, the economic benefits of this technology are quickly eradicated. This work presents the results of a detailed power supply quality survey of 23 small rural industries sponsored by the Canadian Electrical Association and provides a knowledge base on rural power quality and the possible origins of power supply anomalies. The major power quality problems experienced at the various industrial sites are summarized. The results of the survey provide a basis for mitigating actions by the electric utilities and their rural industrial customers to design and operate their electrical systems to minimize the effects of power supply anomalies     

小型高功率氢镍电池的研究

研究了集流方式(二极耳、三极耳、集流盘)对AA 1 300 mAh高功率Ni-MH电池性能的影响,通过充放电、倍率性能、内压特性、循环性能和过充性能等电化学性能的测试优化工艺标准.测试结果表明:三种集流方式都能提高Ni-MH电池的大电流放电容量和放电电压平台,其中集流盘效果最好,三极耳次之,二极耳最差.     

System design via small mobile robots

In the Department of Electrical and Computer Engineering at Northeastern University, USA, an upper-level course has been developed that focuses on the creative design and implementation of a complete engineering system. In this course, the students design small mobile robots to perform a task specified at the beginning of the quarter. The designs are evaluated by how well they complete the specified task. The mobile robot systems are developed through a sequence of subsystem design projects. These subsystems are developed and demonstrated in the laboratory component of the course. The lectures focus on providing the information required to design the system, on the more practical aspects of engineering practice, and on showing how more theoretical concepts learned in other courses can be applied in practice. This course has been offered twice and we deduce from the students' designs and evaluations that it has been successful     

欧司朗推出小巧极品红外LED

欧司朗光电半导体的红外OSLON SFH4715S是迄今为止．光学功率大于1W的红外LED中最为小巧的一款产品。该装置外形尺寸仅为3．75×3．75mm？，因而极易打造出非常紧凑的照明装置，适用在CMOS和CCD摄像机中。欧司朗的奈米堆叠（nanostack）芯片技术及温度稳定的OSLON黑色系列封装，为这款突破性高性能装置打下了坚实的基础。