连续稳定循环的三效吸附式热泵在两种工况下的COP值针算

设计了连续而又稳定循环的三效吸附式热泵单元——三效冷环，由于各吸附床的吸附循环之间具有先后连贯性，因此既避免了吸附床的过热，又消除了热泵输出端的不稳定工作状态，使得热泵系统的ＣＯＰ值、■效率以及各吸附循环的效率比双效和单效系统有显著提高。重点分析了回收和不回收降温、吸附热时三效吸附式热泵比之与其它系统所存在的优越性。     

连续稳定循环的三效吸附式热泵在两种工况下的COP值计算

设计了连续而又稳定循环的三效吸附式热泵单元－三效冷环，由于各吸附床的吸附循环之间具有先后连贯性，因此既避免了吸附床的过热，又消除了热泵输出端的不稳定工作状态，使得热泵系统ＣＯＰ值，Ｙｏｎｇ效率以及各吸附循环的效率比双效和单效系统有显著提高，重点分析了回收和不回收降温，吸附热时三效吸附式热泵比之与其它系统所存在的优越性。     

连续稳定循的三效吸附式热泵单元——三效冷环的设计和原理分析

设计了连续而又稳定循环的三效吸附式热泵单元－－三效冷环，使各吸附床的吸附循环之间具有先后连贯性，既可避免吸附床的过热，又能消除热泵输出端的不稳定工作状态，使得热泵系统的ＣＯＰ值、ｙｏｎｇ效率以及各级附循环的效率均有显著提高。此外，单元化使三效冷环易于长期维持真空度，便于根据余热量的大小进行并联组合成较大的热泵系统。     

连续稳定循环的三效吸附式热泵单元──三效冷环的设计和原理分析

设计了连续而又稳定循环的三效吸附式热泵单元─－三效冷环，使各吸附床的吸附循环之间具有先后连贯性，既可避免吸附床的过热，又能消除热泵输出端的不稳定工作状态，使得热泵系统的ＣＯＰ值、效率以及各吸附循环的效率均有显著提高。此外，单元化使三效冷环易于长期维持真空度，便于根据余热量的大小进行并联组合成较大的热泵系统。     

吸附式热泵的研究与开发

本文综述了吸附式热泵循环理论、工作原理以及描述热泵性能的参数，介绍了近年来吸附式制冷的研究进展及在低温余热回收方面应用的最新开发成果。     

螺旋板式吸附器的应用及连续回热型吸附式制冷循环的实现

吸附式制冷系统中一有的各种吸附器在应用过程中都存在一些缺点。我们设计了一种螺旋板式吸附器，并将其成功地应用在采用活性碳－甲醇为工质对的连续回热型吸附式制冷系统中。实验中该吸附器显示了良好的性能，可以使循环周期大大缩短。通过对建造的连续回热型吸附式制冷系统性能的测试分析，指出了原有连续回热型吸附式制冷系统的弊端，着重讨论了实现连续回热型循环的有效途径。     

降低吸附式制冷系统驱动热源温度的研究进展

吸附式制冷是一种环境友好的制冷方式,可以利用低品位热能提供冷量,因此具有重要的节能意义。目前,吸附式制冷技术在太阳能热利用、工业余热利用等中低温余热领域已有应用,但对低于60℃热源的利用实例较少。降低吸附式制冷系统所需的驱动热源温度是扩大吸附式制冷系统使用范围的重要手段。吸附式制冷系统所需驱动热源温度与系统循环方式、吸附剂性能等因素密切相关。从二级/多级吸附式制冷循环、表面酸性强度与孔结构等影响吸附剂再生温度方面阐述了降低吸附式制冷系统驱动热源温度技术的国内外研究现状。分析结果显示,多级循环吸附式制冷系统可以降低装置的驱动热源温度,但装置结构较为复杂;低再生温度吸附剂能够拓宽吸附式制冷装置的驱动热源温度范围,吸附剂的脱附温度与表面极性、酸性、孔结构等参数有关,对吸附剂进行改性,吸附剂极性弱、酸性低的表面特性有利于降低脱附温度。另外,还介绍了数据中心余热驱动的吸附式制冷技术。开展降低吸附式制冷系统驱动热源温度的研究为低温余热高效利用提供了技术参考。     

燃料电池汽车余热驱动的吸附式空调系统性能分析

针对燃料电池汽车余热驱动的吸附式制冷循环过程吸、脱附特性,采用动态的分析方法,对吸附式制冷系统的主要部件吸附床在不同阶段（等容加热、等压解吸、等容冷却、等压吸附）的工作过程,分别建立了动态方程,并就其制冷系统的蒸发器及冷凝器建立相应的动态方程。利用数值方法对数学模型进行求解．全面而系统地分析了循环周期、热源温度、外界空气温度、空调回风温度以及冷却水进口温度等参数对系统性能的影响。研究结果表明：随着循环周期的延长,单位质量吸附剂制冷功率值存在一个峰值．热源温度的提高、外界空气温度的降低、空调回风温度的升高、冷却水进口温度的降低等均有助于提高吸附式空调系统的性能。     

基本循环吸附式制冷的计算机模拟

在以甲醇-活性炭为工质的基本型吸附式制冷循环中的热量分析中,采用数学软件Matlab模拟计算和理论分析,得出了循环工况对制冷性能和制冷量的影响。     

太阳能吸附式制冷技术进展综述

介绍了太阳能吸附式制冷技术的原理与特点，从吸附剂一制冷剂工质对、系统循环方式以及吸附床三个方面详细说明了吸附式制冷技术的进展。通过综合分析指出，优化系统的设计，尤其是对系统关键部件，如吸附床、冷凝器、蒸发器的优化设计，对太阳能吸附式制冷系统的性能非常重要；其次，应加强对性能稳定、操作简便的无阀系统的研究，同时加大对太阳能吸附式制冷与建筑一体化的研究力度，使之符合建筑一体化的要求。最后分析了太阳能吸附式制冷技术的发展前景。     

Study on heat and mass recovery in adsorption refrigeration cycles

An adsorption air conditioner has been developed and some operation results are summarized. Mass recovery process is proposed to improve the performance. Performance predictions are presented and show that mass recovery can play an important role to better the performance of adsorption refrigeration cycle. Coefficient of performance might be increased or decreased with mass recovery process due to different working conditions. Cooling capacity can be significantly increased with mass recovery process. The cycle with mass and heat recovery has a relatively higher improvement. It can also be seen that the cycle time will be much shorter and it will certainly enhance the cycle with higher cooling/heating power.     

Performance study of a high efficient multifunction heat pipe type adsorption ice making system with novel mass and heat recovery processes

The purpose of this paper is to present the performance analysis of a multifunction heat pipe type adsorption ice maker with activated carbon–CaCl₂ as compound adsorbent and ammonia as refrigerant. For this test unit, the heating, cooling and heat recovery processes between two adsorbent beds are performed by multifunction heat pipes. A novel mass and heat recovery adsorption refrigeration cycle is developed. When mass recovery process is implemented before heat recovery process, the performance of the cycle with novel mass and heat recovery processes is much better than that for the cycle with the conventional mass and heat recovery processes. The experimental results show that the former cycle can increase the coefficient of performance (COP) and specific cooling power (SCP) by more than 17% compared with the latter cycle. In comparison with the basic adsorption cycle, the mass and heat recovery cycle can enlarge the cycled refrigerant mass and reduce the power consumption of boiler; the COP and SCP were improved by more than 11% when the mass recovery time was 20 s, while at the optimal mass recovery time of 40 s, the COP improvements for conventional and novel mass and heat recovery cycles are 43.8% and 68.7%, respectively. It was concluded that the novel mass and heat recovery processes are more beneficial to improve the performance of adsorption refrigeration system in comparison with the conventional mass and heat recovery processes.     

Numerical study of a combined heat and mass recovery adsorption cooling cycle

A new transient two-dimensional model for the simulation of a combined heat and mass recovery adsorption cooling cycle based on the zeolite NaX/water working pair is proposed in this paper. The model describes the transfer phenomena in the adsorber in detail and is solved by control volume method. Internal and external mass transfer limitations which are neglected by many researchers are considered in the model since they have significant effects on the performance of the adsorption cooling cycle. The numerical results show that the combined heat and mass recovery cycle between two adsorbent beds can increase the coefficient of performance (COP) of an adsorption cooling system by more than 47% compared to the single bed cycle. This numerical model can be used in system optimization and design of adsorption cycles.     

A four-bed mass recovery adsorption refrigeration cycle driven by low temperature waste/renewable heat source

The study deals with an advanced four-bed mass recovery adsorption refrigeration cycle driven by low temperature heat source. The proposed cycle consists of two basic adsorption refrigeration cycle. The heat source rejected by one cycle is used to power the second cycle. Due to the cascading use of heat and cooling source, all major components of the system maintain different pressure levels. The proposed cycle utilize those pressure levels to enhance the refrigeration mass circulation that leads the system to perform better performances. The performance of the proposed cycle evaluated by the mathematical model at equilibrium condition and compared with the performance of the basic two-bed adsorption refrigeration cycle. It is seen that the cooling effect as well as COP of the proposed cycle is superior to those of the basic cycle. The performances of the cycle are also compared with those of the two-stage cycle. Results also show that though the cooling effect of the proposed cycle is lower than that of two-stage cycle for heat source temperature less than 70 °C, the COP of the cycle, however, is superior to that of two-stage cycle for heat source temperature greater than 60 °C.     

Physical and operating conditions effects on silica gel/water adsorption chiller performance

Adsorption refrigeration systems are commercially developed due to the need of replacing the conventional systems which utilise environmentally harmful refrigerants and consume high grade electrical power. This paper presents the key equations necessary for developing a novel empirical lumped analytical simulation model for commercial 450 kW two-bed silica gel/water adsorption chiller incorporating mass and heat recovery schemes. The adsorption chiller governing equations were solved using MATLAB® platform integrated with REFPROP® to determine the working fluids thermo-physical properties. The simulation model predicted the chiller performance within acceptable tolerance and hence it was used as an evaluation and optimisation tool. The simulation model was used for investigating the effect of changing fin spacing on chiller performance where changing fin spacing from its design value to minimum permissible value increased chiller cooling capacity by 3.0% but decreased the COP by 2.3%. Furthermore, the effect of generation temperature lift on chiller performance and the feasibility of using it as a load control tool will be discussed. Genetic Algorithm optimisation tool was used to determine the optimum cycle time corresponding to maximum cooling capacity, where using the new cycle time increased the chiller cooling capacity by 8.3%.     

太阳能固体吸附式制冰机热动力学性能分析模型及实验

分析了太阳能固体吸附式制冷装置中吸会床的传热传质计算过程,给出了求解模型的具体方法,运用数值传热学的方法,计算了在一定日照国徽能量条件下,系统装置的吸附床内的温度场分布,实验表明,所建立的模型能对太阳能固体吸附式制冷装置进行了性能动态模拟,为系统装置的优化设计提供了参考。     

Dynamic characteristics of a novel adsorption refrigerator with compound mass‐heat recovery

A three‐effect heat pipe (heat pipe heating, heat pipe cooling and heat pipe heat recovery) adsorption refrigeration system using compound adsorbent (calcium chloride and activated carbon) was designed. The dynamic characteristics of mass and heat pipe heat recovery were studied. The results show that mass recovery and heat pipe heat recovery can improve (specific cooling power) SCP and (coefficient of performance) COP greatly. The averaged SCP of the cycle with mass recovery and the cycle without mass recovery is 502.9 W/kg and 436.7 W/kg at about 30 °C of cooling water temperature and ?15 °C of evaporating temperature. The corresponding COP is 0.27 and 0.24 respectively. Copyright © 2011 John Wiley & Sons, Ltd.     

固体吸附式冷管循环工作过程的动态模拟与分析

针对余热驱动吸附式冷管单元(直径16mm,总长1020mm)制冷循环过程的变压吸/脱附特性,采用线性驱动力(LDF)模型,建立了动态的传热传质数学模型。对吸附式冷管的主要部件——吸附器和冷凝/蒸发器在加热解吸和冷却吸附不同阶段的工作过程,分别建立了耦合的动态方程。对所提出的模型进行分析和合理简化后,利用数值方法对模型进行了求解,获得了冷管单元吸附器、冷凝/蒸发器的循环工作参数的动态变化规律,计算结果与实验结果较好地吻合。为吸附式冷管单元及其组合式制冷系统进一步的优化设计和实用化的改进研究提供了重要参考。     

Performance Comparison of Three-Bed Adsorption Cooling System With Optimal Cycle Time Setting

This article presents the optimal cycle time and performance of two different types of silica gel–water-based three-bed adsorption chillers employing mass recovery with heating/cooling scheme. A new simulation program has been developed to analyze the effect of cycle time precisely on the performance of the systems. The particle swarm optimization (PSO) method has been used to optimize the cycle time and then the optimum performances of two chillers are compared. Sensitive analysis of cycle time has been conducted using the contour plot of specific cooling power (SCP) with driving heat source temperature at 80°C. It is found that the center point of the contour indicates the maximum SCP value and optimal cycle time, which are comparable with the quantitative values obtained for the PSO method. Both three-bed mass recovery adsorption cycles can produce effective cooling at heat source temperature as low as 50°C along with a coolant at 30°C. The optimal SCP is similar for both cycles and is greater than that of the conventional two-bed adsorption system employing the same adsorbent–refrigerant pair. Consequently, the proposed comparison method is effective and useful to identify the best performance of adsorption cycles.     

Thermodynamic analysis and performance study for adsorption refrigeration cycle driven by a fuel cell electric vehicle waste heat

Three kinds of adsorption refrigeration cycles are analyzed in this paper, a two‐bed continuous cycle, an adiabatic mass recovery cycle, and an isothermal mass recovery cycle. Operating parameters (including desorption temperature, adsorption temperature, cycle adsorption rate, COP, and period refrigerating capacity) with the change of the evaporating temperature, condensing temperature, heat capacity ratio, and heat resource temperature are discussed. The analysis indicates that performance differences between the mass recovery cycle and the two‐bed continuous cycle are reduced with an increasing of evaporating temperature and heat source temperature. By increasing the heat capacity ratio, COP values for the three kinds of cycle decrease. When the heat source temperature is between 70 and 90°C, the performance of the isothermal mass recovery cycle is best. Through study, this paper puts forward that the isothermal mass recovery cycle is the best cycle for adsorption refrigeration systems driven by fuel cell electrical vehicle waste heat. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res, 39(7): 523–538, 2010; Published online 16 July 2010 in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/htj.20315