环境湿度对卧式陈列柜热负荷影响的数值分析

随着大型超市的不断发展，陈列柜的使用量越来越大，陈列柜的节能也越来越重要。采用雷诺应力模型对某型卧式陈列柜的温度场和湿度场进行了仿真计算和实验验证；并通过实验的手段，对环境湿度对卧式陈列柜热负荷的影响进行了研究。     

冷藏柜制冷系统优化设计及试验研究

冷却肉冷藏陈列柜越来越得到人们的广泛认同和欢迎。对冷却肉冷藏柜进行了系统分析，特别是USH67MR-050S型冷藏陈列柜，对其制冷系统从压缩冷凝机组、蒸发器换热面积、制冷系统工质充注量、毛细管长度的确定等几方面进行优化设计及试验研究，从而得到USH67MR-050S冷却肉冷藏柜的最佳配置。     

超市室内温度分布测试与分区平衡温度分析

超市内陈列柜冷量的泄露容易引起其周边的气温下降,从而造成室内热舒适性降低,为此有必要详细分析陈列柜周边气温对超市室内温度分布的影响。选择典型超市,对其夏季室内温度分布进行了测量,发现超市环境中存在着明显的温度分布不均现象,进而导致电能的浪费。依据超市室内温度分布不均的特点,将其划分为三个区:陈列柜区、临近陈列柜区和远离陈列柜区。定义供冷与供热状态下陈列柜区的对比温度为陈列柜区温度与临近陈列柜区气温的比值,再根据热力学第一定律以及热传递原理,分别导出陈列柜区开始供冷与供热的对比温度计算表达式。引入分区平衡温度的概念,绘制出供冷与供热工况下,陈列柜区的两条分区平衡温度曲线。分析表明,陈列柜区的能耗控制需通过调整陈列柜泄露冷量与热回收量以及该区内空调或电加热开启之间的平衡来实现。     

集中送风式陈列柜的节能策略

分析了集中送风式陈列柜"制冷机送风"和"环境送风"的弊端,提出了"联合送风"方式。在此基础上,归纳出集中送风式陈列柜的节能策略,并对其进行了模拟计算分析。分析表明,集中送风式陈列柜随室外环境温度改变采取不同的节能策略,既提高了能量效率,又拓展了其应用范围。     

导流格栅对冷藏陈列柜性能影响的试验研究

在M3工况下对敞开立式食品冷藏陈列柜安装导流格栅前后的冷藏性能进行试验研究,分析了开式食品冷藏陈列柜加装导流格栅前后陈列柜内温度及能耗的变化规律。试验结果表明:在搁架前端加装导流格栅能够显著改善风幕性能,达到节能的效果。在陈列柜搁架安装导流格栅后的后排食品包平均温度都在不同程度上高于安装之前的食品包平均温度。且搁架末端设置空气导流格栅比未设置导流格栅的陈列柜的电能消耗节省约23%。     

室内环境对自然冷源陈列柜冷藏性能影响实验研究

通过试验研究的方法,将自然冷源引入冷藏陈列柜,在完全利用室外冷源对陈列柜柜内进行供冷的运行模式下,保持风幕送风速度为1.1m/s,室外送风温、湿度分别为1.0℃、60%,室内湿度为60%不变,调节室内不同的温度,观察柜内食品包温度变化分布,研究陈列柜食品包冷藏特性。实验结果表明:与利用制冷系统供冷的传统陈列柜相比,自然冷源供冷使柜内温度分布均匀性得到很大提升,自然冷源陈列柜1~5层同侧食品包温差不超过1.5℃,但是每层内侧和外侧食品包温差在2.5~3.0℃。在此送风条件下,保证室内温度在22.0℃以下可以满足柜内食品贮藏温度0.0~7.0℃的要求。风幕参数变化规律:随着食品包前端距离的增加相对湿度呈现先增大后减小,最后稳定于和室内湿度相等的趋势。风速和温度呈逐渐减小的趋势,且变化速率不断减小。     

卧式螺旋管气液两相流摩擦阻力特性研究

在２种不同尺寸的卧式螺旋管内进行了油－气、气－水两相流和油－气－水三相流摩擦阻力的实验研究，在对实验结果和前人有关研究进行分析比较的基础上，给出了各流动条件下摩擦阻力的计算公式，为进一步研究提供了依据和基础。     

商用陈列柜的可靠性和能耗

分析了影响商用陈列柜可靠性和能耗的因素，阐明了温度对冷冻负荷和冷冻能力的影响，对比了多台并联机组与单台机组的差别，为实际使用和选型奠定了基础。     

闭式冷藏冷冻陈列柜热工计算若干问题的探讨

冷藏冷冻陈列柜是食品冷藏链中最终环节的制冷设备。它确保食品了销售过程中的新鲜卫生和食品原有的色香味特色外,还兼有美观的外型和色彩鲜艳的照明来突出商品的展示效果,美化商店、菜场面貌,提高营业的销售率。因此,国外冷冻陈列柜得到了普遍地应用,产量每年都有迅猛的增长[1]。随着四化建设和人民生活水平提高,商业销售方式的变化,我国已进入了使用冷冻陈列柜的阶段,许多冷冻机厂也纷纷进行了试制,有的已生产了产     

卧式快装锅炉炉墙保温不良原因分析及改进措施

本文对卧式快装锅炉炉墙和保温层常见故障的原因进行分析，提出解决和改进的措施，对卧式快装锅炉的生产运行、维修及节能具有一定的意义。     

Application of an effective strategy for optimizing the design of air curtains for open vertical refrigerated display cases

This paper presents a novel strategy for optimizing the design of air curtains for open vertical refrigerated display cases which is based on an air curtain two-fluid of cooling loss (CLTF) model and a support vector machine (SVM) algorithm. A model for air curtain cooling loss, one important performance factor of display cases, is proposed. To verify the air curtain cooling loss and determine which design parameters significantly influence the performance of air curtains in open vertical display cases, the CLTF model was built to study the flow and transfer of heat through air curtains used in such display cases. After the object function for cooling loss is constructed, it is solved using an SVM algorithm with different input design parameter combinations. As a result, the predicted cooling loss is reduced by 19.6%. After being validated using experimental data, the TEC/TDA of optimum display case is found to be reduced by 17.1%. The experimental results show this strategy to be an effective method of optimizing the air curtain design.     

Performance simulation of refrigerated display cabinets operating with refrigerants R22 and R404A

This paper describes the analysis and performance comparison of a display cabinet system using refrigerant R404A and its substitute refrigerant R22. The model of the display cabinet is developed at steady state and integrated from three main component sub-models, air-cooling finned-tube evaporator, air curtain and display cabinet body. The evaporator model is built up based on the distributed method, which can simulate the heat exchangers with different circuit structures. The frost effect on the performance of the evaporator is included in the model. The correlations for the heat transfer and pressure drop calculations of both air and refrigerant sides are purposely selected in the evaporator model. In addition, the evaporator model has been validated with experimental results at steady states from published literature. Several correlated functions from the detailed numerical solution are used for the model of the air curtain. Some simplifications are also utilized for the model of display cabinet body. The performance simulation and comparison of the display cabinet using refrigerants R404A and R22 are carried out at different indoor ambient conditions especially at varied ambient air humidity to mimic the actual indoor space conditions in super stores. Some significant results such as the comparison of cooling load requirement for different refrigerant display cases have been obtained from the simulation, which can significantly contribute to the optimal cabinet design and operating analysis.     

伪彩色技术在超声无损检测中的应用

人眼对彩色的变化远比对灰度的变化敏感,但目前的超声无损检测结果的显示大多仍采用灰度图象方式.通过将伪彩色技术应用于超声无损检测过程,实现了超声检测缺陷结果图象的伪彩色显示,提高了无损检测结果的直观性,增强了对缺陷的表达能力.     

超市空调的室内设计参数与总能耗

目前有关超市的室内设计温、湿度对环境舒适性影响的研究匮乏，对超市空调和制冷的相互作用往往忽视或误解。在综合分析了超市室内温度、相对湿度对超市环境舒适性、超市空调能耗、陈列柜能耗的影响后，找出了超市夏季空调最佳温、湿度设定点。     

超市空调室内设计参数与总能耗分析

针对目前室内设计温、湿度对超市环境舒适性影响的研究较少,以及在超市能耗的研究中,对超市空调和制冷的相互作用的忽视甚至误解的现状,本文将综合分析超市室内温度、相对湿度对超市环境舒适性、超市空调能耗、陈列柜能耗的影响,找出上海超市夏季空调最佳温、湿度设定点。     

Photovoltaic display module in a mobile GPS

We have developed a mobile global positioning system (GPS) that operates on just photovoltaic (PV) cells. The system receives wireless signals from satellites and shows one's present location accurately on a map without the need for a battery. A PV display module, which combines a transparent LCD with a-Si PV cells and has a power generation function, is added to ordinary PV cells to increase the total amount of power generated. The PV display module enables 40% more power generation than a system without the module.     

Heat Transfer and Pressure Drop Under Dry and Humid Conditions in Flat-Tube Heat Exchangers With Plain Fins

Flat-tube heat exchangers could be an interesting alternative to make indirect cooling of display cabinets more energy-efficient. This application involves low air velocities in combination with condensation of water vapor on the air side, so plain fins could be suitable. Two different heat exchangers having flat tubes and plain fins on the air side were evaluated experimentally. One of the heat exchangers had continuous plate fins, and the other had serpentine fins. The performances during dry and wet test conditions were compared and related to theoretical predictions for different assumptions. The influence of air velocity, air humidity, and inclination angle was investigated. The results show that, in most cases, the heat transfer performance is somewhat reduced under wet conditions in comparison with dry test conditions, and that wet heat transfer surfaces lead to an increased pressure drop. At the lower air velocity range that was investigated, the heat exchanger having continuous plate fins drained better than the one with serpentine fins.     

基于MapX的电力系统GIS人机交互设计

应用基于地理信息系统(GIS)的电力系统可视化界面开发方法,使用MapInfo软件,设计绘制包括基础地理层、发电厂层、变电站层、220 kV输电线路层、500 kV输电线路层的GIS图.在此基础上,实现基于MapX的电力系统GIS人机交互基本功能及高级功能,基本功能包括空间功能、查询功能、详细数据展示功能、专题图功能、鹰眼图功能、等高线图功能、3D可视化功能,高级功能包括关联多屏显示功能、自适应调节功能.在整个系统中,基本功能可以较为简单地进行实现;高级功能突破了简单的二次开发限制,针对性更强,且具备了更专业的人机交互功能.依据电力系统中不同的使用特点和需求,还可以在此基础上开发出更多的其他高级功能.在对电网数据进行管理、分析和维护时具有显著的效果.