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《中国光学与应用光学文摘》2005,(1)
TK511.3 2005010490 太阳能冷管的研究及其进展=Research of solar cooling tube and its advancement[刊,中]/刘震炎(上海交通大学机械与动力工程学院.上海(200030)),徐海峰…∥太阳能学报.-2004,25(1).28-32 太阳能冷管以沸石分子筛-水为工质对,在一根玻璃管内完成吸附式制冷循环,一根冷管即为一个制冷单元, 成功地解决了太阳能吸附式制冷技术难以转化为成果的 相似文献
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设计了一种新型平行流铝扁管吸附床结构,搭建了吸附式制冷实验台。通过实验研究不同运行参数下的吸附式制冷系统性能差异,比较不同热源和冷源温度、换热流体流量下吸附式制冷系统COP的变化。结果表明,当冷、热源温度为10℃和60℃,换热流体流量为0.26 kg/s时,新型吸附式制冷系统COP达到最大值0.35。当冷源温度在20℃附近时,增大热源温度可有效提高吸附式制冷系统COP,并且换热流体流量越大,增加的幅度越明显;当换热流体流量在0.13~0.26 kg/s范围内时,系统COP随着冷源温度的增大剧烈下降,并且换热流体流量越小,下降趋势越显著;当热源温度在55~60℃范围内时,COP随着换热流体温度的增大明显增大,并且冷源温度越高,COP增大的趋势越明显。 相似文献
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吸附式制冷系统中吸附床材料热容对系统运行COP的影响分析 总被引:2,自引:0,他引:2
1前言在吸附式制冷系统的理论运行研究中,很少考虑吸附床材料的影响。实际上由于吸附式制冷系统的非连续性,吸附床材料的热容对实际系统运行性能的影响是非常大的。这个影响体现在系统不断地加热和冷却过程中所损失的吸附床材料的显热热量,这个热量的大小直接受吸附床本身设计的影响,另外还受到系统运行过程的影响,如:系统运行的解吸温度、回热所进行的程度等。由于该系统中通常所用的吸附剂均属多孔性材料,其特点是热导率小,密度低,要满足一定的制冷功率,所设计的吸附床往往很大,另外为增强吸附床内的热传递,加快吸附床的冷却… 相似文献
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设计了一种以太阳能为驱动力,利用渗透压将水分从蒸发器端传输到冷凝器端的压差式吸附制冷机.水分先在蒸发器端被吸附板吸收,再通过渗透压自动运输到最后环节段,并被膨胀物质间歇式地挤压出吸水材料,进入冷凝器,从而保证水分不断从蒸发器抽出,产生制冷效果.通过改变太阳能制冷系统的四通换向阀的开启方向,实现吸附式制冷系统的连续制冷. 相似文献
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固体吸附式制冷是一种可直接利用余热作为驱动热源和使用天然制冷剂的制冷方式,它对环境保护与节约能源具有重要意义,吸附式制冷技术目前已成为国际上普遍关注的一个学术方向。其中,采用其他以热能为动力的制冷循环方式与固体吸附式联合制冷在制冷领域已成为一个重要方向。首先介绍非单一吸附式制冷方式的总体研究进展,随后对其未来研究和应用发展方向作了展望。 相似文献
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P. A. Patil 《实验传热》2013,26(2):77-91
Performance analyses of an HFC-404A refrigeration system for a smooth U-tube condenser and a micro-fin U-tube condenser are carried out for various operating conditions. This article mainly reports performance testing of the above-mentioned condensers for various operating parameters and their effect on the performance of refrigeration systems. The condensers used are shell and U-tube types, with refrigerant through a tube and cooling water through a shell. It also reports the performance enhancement of the system using a micro-fin tube condenser relative to a smooth-tube condenser system. The cooling capacity of the system is increased by 10%, and the coefficient of performance of the system is improved up to 17% using a micro-fin tube condenser. 相似文献
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《Heat Recovery Systems and CHP》1990,10(1):61-70
Mexico possesses large amounts of geothermal brine at temperatures which are too low to enable electricity to be generated efficiently and economically. Most of the geothermal fields in Mexico are located near important agricultural areas. Perishable food losses in Mexico, resulting from inadequate handling and cold storage facilities, vary from 35 to 50%. In order to prove the technical feasibility of operating heat-driven absorption cooling systems on low enthalpy geothermal energy, a prototype ammonia/water absorption cooler was installed in the Cerro Prieto geothermal field, where the ambient temperatures exceed 40°C and the cooling water temperatures reach 30°C. The unit has operated successfully with evaporative cooling loads exceeding the design value. The experimental data obtained will provide an excellent basis for the design of large scale heat-driven absorption refrigeration systems. 相似文献
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变频压缩机空调系统的理论分析及实验研究 总被引:3,自引:0,他引:3
变频空调器是由变频压缩机驱动的空调系统,压缩机通过变频调节其转速使压缩机单位时间内的排气量变化,从而达到调节制冷量的目的。本文提出了变频空调器制冷系统的原理和设计方法,具体给出了制冷量和压缩机频率的关系方程,并从理论和实验两方面对变频空调器制冷系统进行了分析,得到了频率曲线图,为变频空调器制冷系统的设计提供了依据。 相似文献
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《Heat Recovery Systems and CHP》1993,13(4):363-371
Since 1979, long-life, reliable heat-powered sorption refrigeration systems have been developed for spacecraft use at the Jet Propulsion Laboratory (JPL). JPL has successfully built and tested a series of cryogenic sorption refrigeration systems for spacecraft sensor cooling and is presently assembling a −263°C (10K) hydride sorption refrigerator, which will fly on the Space Shuttle in 1994. With the addition of novel regenerative heating techniques, this same technology has more recently been applied to design high efficiency, ground-based adsorption heat pumps. Using actual sorption isotherm data and detailed analytic thermal computer models, analysis has predicted that the cooling and heating COPs will be significantly better than for any other single stage, heat-powered heat pump. Specifically the cooling COP (COPc) with the new regenerative system using ammonia is predicted to be as high as about 1.16. Recent tests on a single carbon sorbent canister compressor have been performed with R22, R134a, and ammonia. Transient thermal response of the sorption compressor has compared well with computer predictions. With ammonia, the total amount of average cooling from the 0.51 kg bed of carbon has been measured to be about 1038 Btu h−1 (304 W) for a 6 min full cycle including both heating and cooling. 相似文献
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水平管降膜蒸发器传热优化研究 总被引:1,自引:0,他引:1
基于分布参数方法,对大型制冷系统中的水平管外降膜蒸发进行了传热优化数值模拟计算.在计算中,分析了饱和的液态制冷剂R134a在水平的铜管束外流动蒸发的换热特性.模型考虑了不同的管子类型和2流程不同管程布置对蒸发器换热特性的影响,结果表明,蒸发器采用Turbo-EHP管的性能高于其它管;不同管程布置对蒸发器性能的影响比较大,其中,下进上出管程布置的换热性能优于其它管程布置.同时,本文考虑了传热管外"干斑"对换热的影响.本文结论对于大型制冷系统中的降膜蒸发器传热优化设计具有指导性意义. 相似文献