山东龙口60000m~3气调冷库库体的设计

果蔬的气调贮存是世界上最先进最有效的长期贮存的方法之一,它可以最有效地保持果蔬的原有品质。库体是气调冷库的重要组成部分,保温隔汽是库体的基本功能之一,作为气调冷库更重要的是库体的气密性,这是气调冷库的关键所在。气密性能的好坏直接关系到气调冷间气体成份的调节速度和波动幅度,影响到果蔬的贮存质量和贮存成本。如何保证库体的气密性,国内气调库在这方面的技术较国外水平尚有一定差距,目前国内较成功的气调冷库多为进口国外产品,现就我厂成功设计制造安装的山东龙口60000m~3气调冷库库体作一浅谈。     

产地果蔬简易冷库存在的问题及对策

针对近几年技术推广中，产地果蔬简易冷库中发现的问题，分析说明造成产地果蔬冷库能耗增大的原因，并提出相应的解决办法。是对《暖通空调》1988年第1期中，“果蔬储存简易小冷库设计总结”一文进行的补充论述。     

产地果蔬简易冷库存在的若干问题及对策

针对近几年技术推广中,产地果蔬简易冷库中发现的问题,分析说明造成产地果蔬冷库能耗增大的原因,并提出相应的解决办法.     

果蔬冰温保鲜冷库的设计要点

阐述了果蔬冰温保鲜冷库的结构设计,并与传统的冷库送风方式进行了比较;介绍了冷库的制冷系统设计、气调设备配置等设计要点。实践证明,此种冰温库能更好地保持果蔬的新鲜度,并延长储存时间。     

气调冷库加湿分析与软件算法

气调冷库内的果蔬在被冷却的同时,由于自身呼吸热和干冷空气的吸湿作用会不断失去自身水分,这不但会加速自身营养成分的流失和破坏,而且会减少自身的质量,造成较大的经济损失。因此,对气调冷库内的果蔬及时、准确地加湿是一项非常重要的技术工作。本文分析阐述减湿和加湿的原理及过程,并提出修正的湿空气物性参数模型方程,依据牛顿迭代算法,开发冷库果蔬加湿计算机辅助计算软件,其计算结果与现有冷库工作过程的实测数据相吻合。     

动态冰浆蓄冷湿冷技术在果蔬冷藏中的应用前景分析

本文介绍了湿冷冷藏技术对果蔬贮藏品质的影响,以及湿冷技术与冰蓄冷技术结合的优点,提出将动态冰浆蓄冷技术应用于果蔬湿冷冷库制冷系统中,并介绍了所研制的动态冰浆蓄冷湿冷冷库制冷系统构成及其优缺点。     

试论国内外果蔬冷库的新发展

一、国外果蔬冷库发展的新经验近年来,欧、美、日本等发达国家的果蔬贮存保鲜技术发展很快。果蔬冷库在其数量不断增长的同时,制冷装置设计方面不断有所创新,突出地表现在以下几个方面: (一)予冷装置的采用予冷的目的是使收获后的果蔬产品快速冷却到适当的温度,使食品体内的消耗限于最小程度。产区设库,就地予冷,就地贮藏是欧美发达国家建库的主要特点之一。     

准球形葡萄预冷时间的研究

果蔬预冷是冷藏链中一个重要环节，适当的预冷时间能保证果蔬质量。通过对巨峰葡萄在预冷时的传热分析，建立了集总参数法模型来估算葡萄中心温度达到冷库温度时所需要的时间，并通过实验进行了验证。结果表明当冷库内空气流速达到一定时(大于1．1m/s)，采用定性尺寸R，集总参数法能够很好地估算葡萄预冷时间，为农业生产中形状类似于葡萄的果蔬预冷时间提供了依据。     

气调冷库室内环境浅析

论述了气调冷库发展的当今形势 ,室内环境对储存果蔬产品的影响 ,分析了营造什么样的环境才能适于果蔬产品高质量长期储存。     

冰蓄冷和湿空气保鲜果蔬冷库新技术

不同于传统的冷库，采用冰蓄冷和湿空气保鲜的新型冷在欧洲和美国已广泛应用于泛8应用于果蔬、花卉的保鲜，本文阐述工作原理，优点和应用实例。     

低温冷库的温度要求与能效分级探讨

冷冻食品在低温冷库中贮藏是食品冷链中的重要环节,低温冷库的库温不均匀度、库温波动对货品品质有非常重要的影响。在保证正确的库温、合理的库内温度不均匀度和库温波动范围的前提下,对冷库能耗进行评价才有意义。制订低温冷库温度要求和对低温冷库的能效进行分级,将在规范低温冷库的设计和建设,提高冷库的货品品质,保证食品安全,降低冷库能耗,提高冷库的综合效益等方面发挥积极的作用。     

大型冷库计算机网络自动控制系统

根据冷库制冷工艺的要求,提出-种基于现场总线技术的冷库计算机网络自动控制系统,并详细介绍了自动控制系统的组成、系统功能和关键技术.解决了传统DCS控制系统中存在的问题,减少了系统布线,提高了冷库运行的可靠性和自动化水平,降低了能耗.     

基于非稳态RANS模型的冷库库门渗风研究

伴随冷库总量的快速增长,冷库的能耗问题已越来越受到关注。库门渗风作为冷库的一项占比很大的热负荷是冷库能耗研究的一个重点。本文采用非稳态RANS模型对库门渗风建立了动态模拟模型,利用对一座库高和门高之比为2:1的冷库不同库内外温差和冷风机运行模式下的实测数据进行验证,结果表明：所建模型预测的渗风量、测量点当地风速和温度的数值和变化趋势都与实验值有较好的吻合,在开门时间40 s内渗风量模拟误差在±10%以内。利用该模型对渗风的特性和机理进行了模拟分析,结果表明,受风机水平方向风场影响,风机开时库内温度均比风机关时低。库内外空气密度差较小,库内冷空气受重力的影响不大,因此渗风量随开门时间呈线性变化。     

欧洲冷库能效在线评估研究及分析

提高冷库能效是欧盟的一个研究项目,该项目利用互联网开发了能效在线评估工具/平台。本文介绍该在线评估软件的内容、设计思路与基本操作步骤以及该软件在欧洲3个冷库试用的初步结果,并对其在国内冷库的应用进行初步分析。结果表明,冷库能效在线评估是一种十分有效的节能工具。指出我国应借鉴其方法,开发适合我国冷库的能效在线评估工具。     

Evaporative condenser control in industrial refrigeration systems

This paper is a result of a research project which focused on optimization of an existing industrial refrigeration system for a large two-temperature level cold storage distribution facility located near Milwaukee, Wisconsin. This system utilized a combination of single-screw and reciprocating compressors (each operating under single-stage compression), an evaporative condenser, and a combination of liquid overfeed and direct expansion evaporators. A mathematical model of the existing system was developed. The model was validated using experimental data recorded from the system. Subsequently, the model served as a tool to evaluate alternative system designs and operating strategies that lead to optimum system performance. The methods, analysis, and results presented in this paper focus on evaporative condenser sizing and head pressure control. Operating system head pressures that minimize the energy costs of the system were found to be a linear function of the outdoor wet-bulb temperature. A methodology for implementing the optimum control strategy is presented. Simulation results for the annual performance of the refrigeration system investigated in this project show a reduction in annual energy consumption by 11% as a result of the recommended design and control changes.     

Hermetic compressors — a case study

Since the energy crisis, Danfoss have been working systematically on their hermetic compressors for household refigerators and freezers. Significant savings in energy consumption have been achieved, both from improvements to existing designs and from a new design of the smallest compressors.The improvements and results achieved are presented here.     

Fuzzy control of the compressor speed in a refrigeration plant

In this paper, referring to a vapor compression refrigeration plant subjected to a commercially available cold store, a control algorithm, based on the fuzzy logic and able to select the most suitable compressor speed in function of the cold store air temperature, is presented. The main aim is to evaluate the energy saving obtainable when the fuzzy algorithm, which continuously regulates the compressor speed by an inverter, is employed to control the compressor refrigeration capacity instead of the classical thermostatic control, which imposes on/off cycles on the compressor that works at the nominal frequency of 50 Hz. The variation of the reciprocating compressor speed is obtained by controlling the compressor electric motor supply current frequency in the range 30–50 Hz, as it is not possible to consider values smaller than 30 Hz because of the lubrication troubles due to the splash system. In this range, two among the most suitable working fluids proposed for the R22 substitution, such as the R407C (R32/R125/R134a 23/25/52% in mass) and the R507 (R125/R143A 50/50% in mass) are tested. Comparing the compressor speed fuzzy control with the classical thermostatic control, frequently used in the cold stores and in other refrigeration systems, the experimental results show a meaningful energy saving equal even to about 13% when the R407C is used as a working fluid. In particular, to explain from the energy saving point of view the best performances of the refrigeration plant when the compressor speed varies, an exergetic analysis is realized. Besides, with regard to the inverter cost, the pay-back period determined is more than acceptable for the plant size examined.     

高静压风机盘管加新风系统取代热空气幕的应用

简要探讨了严寒、寒冷地区小空间建筑外门采用高静压风机盘管结合新风的系统形式；与热空气相比，该系统可以大大减小风量，降低能源消耗，可以在一定范围内取代热空气幕系统；探讨了设置该系统的几个问题；采用CFD技术对采用该系统的哈尔滨某商场小商服进行了数值模拟。     

Comparative performance evaluation of positive displacement compressors in variable-speed refrigeration applications

This paper presents the results of investigations into the performance of positive-displacement refrigeration compressors for variable-speed capacity control applications. Compressors tested include an open-type reciprocating, a semi-hermetic reciprocating and an open-type rotary vane. All three compressors were tested under constant and variable head-pressure operating conditions. The results indicate that all three compressors were designed for maximum efficiency at nominal speed. At constant head-pressure only the open-type compressor exhibited an improvement in the COP at reduced speeds. With variable head-pressure-control all three compressors showed an increase in the COP with a reduction in speed. The results of an energy analysis carried out based on the experimental results and weather conditions for two locations representing temperate and warm weather conditions showed that all three compressors when operated at variable speed offer energy savings compared to their fixed-speed counterparts. The analysis has shown the open-type reciprocating compressor to be the most efficient system offering 12% savings when operating in a temperate climate and 24% savings when operating in a warm climate.     

夏热冬冷地区居住建筑冷热源经济性分析

采用改进的温频法进行负荷计算,针对夏热冬冷地区某居住建筑的冷热源方案进行全寿命周期经济性分析。结果表明,采用地源热泵方案经济性最好,比空气源热泵节省费用约7.5%,比冷水机组加燃气锅炉方案节省费用约21.2%。同时,输配能耗占总能耗比重约20%,应优化设计输配系统,降低输配能耗。采用地源热泵方案时,如能采用与冷却塔的复合运行模式,其运行能耗将进一步降低。