塑料管单效溴化锂吸收式制冷机理论研究

分析了塑料管单效溴化锂吸收式制冷机的理论循环，对塑料管单效溴化锂吸收式制冷机进行了热力计算和传热计算，为塑料管单效溴化锂吸收式制冷机的结构设计及实验研究提供理论依据。     

朗肯循环耦合双效溴化锂吸收式制冷系统建模及性能分析

为提高船用柴油机余热回收效率,利用MATLAB对朗肯循环及双效溴化锂吸收式制冷系统进行建模及热力学分析,确定朗肯循环热效率的影响因素及双效溴化锂吸收式制冷阶段中废气温度、高压发生器温度、低压发生器温度对制冷量和性能系数的影响。结果表明：朗肯循环最佳工质为水;升高初温、初压和降低背压可提高朗肯循环热效率;随着废气温度增加,双效溴化锂吸收式制冷系统的制冷量增加,制冷性能因数降低;随着高压发生器温度升高,制冷量降低,制冷性能因数降低;随着低压发生器温度降低,制冷量增加,制冷性能因数降低;应根据不同环境及场合要求,调整双效溴化锂吸收式制冷系统相关参数。     

电厂循环水余热在供热系统中的利用

通过对电厂发电过程中能量利用及损失分析,发现在发电过程中全年有大量低品位能量,通过冷却塔散发到环境中。现提出溴化锂吸收式热泵系统余热回收利用的方式,将循环水中低品位余热回收用于供暖。同时,介绍了溴化锂吸收式热泵余热利用系统,计算余热回收系统的经济效益,并对节能效果进行了分析,最终通过实践证明改造后的系统运行稳定,节能效果显著,经济效益巨大。     

工业余热氨水吸收式制冷系统研究现状与发展趋势

由于我国节能减排政策的引导,工业余热氨水吸收式制冷系统以其节能减排、制冷效果好等优点越来越引起人们的关注。工业余热氨水吸收式制冷系统的研究主要集中在新型工质对的寻求、强化传热传质、优化制冷循环系统的研究等方面,特别是吸收器的吸收强化及活性剂的研究,成为工业余热氨水吸收式制冷系统的研究热点,通过对以上内容进行了详细分析,并指出今后的发展趋势。     

基于有限元方法的溴化锂降膜吸收传热传质的数值研究

吸收器是吸收式制冷系统的重要部件.溴化锂溶液的降膜吸收是吸收器中最常见的传质传热形式之一.通过对溴化锂溶液在降膜吸收过程中传质和传热特性的分析,使用基于有限元法的COMSOL Multiphysics软件,建立了溴化锂溶液和水蒸汽降膜吸收的物理数学模型,计算了液膜内部温度和质量分数的分布、界面处传质通量、界面处传热通量...     

利用发动机余热驱动的汽车制冷空调系统

常见的汽车空调在制冷过程中需要压缩机介入,增加了能源消耗和尾气的碳排放量。结合汽车散热器和吸收式制冷系统,提出一种利用发动机余热驱动的吸收式制冷空调系统。系统将吸收式制冷发生器分为高、低温两部分,利用上、下水室温差实现两级解吸,实现汽车内部的快速制冷降温,并选用R134a与[Hmim][Tf₂N]替代传统制冷工质对,简化制冷装置,提高循环倍率。结果显示：与传统制冷空调相比,设计的制冷空调系统对能源的依赖度降低,制冷性能好,实现了节能减排的目的。     

溴化锂吸收式制冷技术在余热回收中的研究

本文对溴化锂吸收式制冷技术在燃汽轮机电站空气冷却和柴油机排气的余热利用等节能方面的应用进行了研究。     

强化传热技术在溴化锂吸收式制冷机上的应用

针对国内溴化锂吸收式制冷机组结构笨重、体积庞大、金属耗量多等缺，指出了溴化锂吸收式制冷机采用强化传热技术的必要性。利用理论分析和实验研究结果，总结出了溴化锂机组各传热设备中应分别采取的强化传热手段。根据机组中各换热器的传热机理和传热过程，相应采取不同的传热技术，可使溴化锂吸收式制冷机组节省有色金属３５％以上，体积减小５０％以上。     

基于吸收式热泵的循环水余热利用技术在大型抽凝机组热电联产中的应用

为了降低燃煤电厂的能耗,该文提出了一种基于吸收式热泵的循环水余热利用技术,提取发电机组的循环水余热用于城市供暖,在热电厂内设置溴化锂吸收式热泵站,利用机组循环冷却水作为热泵的热源水,提取余热加热热网水,从而显著提升热电厂的供热能力及热效率,进一步降低综合供电煤耗,实现节能减排的目的.     

工业余热氨水吸收式制冷系统优化研究

为了提高工业余热氨水吸收式制冷系统的综合性能,根据系统优化的三大原则,选择出影响系统性能的7个关键参数,并采用VC++编制了工业余热氨水吸收式制冷系统参数优化软件。该软件可以根据用户需要,快速准确地计算出优化后的参数,经优化软件计算得出以最小面积性能比为优化目标时,优化结果能够有效地提高系统的综合性能。     

Using engine exhaust gas as energy source for an absorption refrigeration system

This work presents an experimental study of an ammonia–water absorption refrigeration system using the exhaust of an internal combustion engine as energy source. The exhaust gas energy availability and the impact of the absorption refrigeration system on engine performance, exhaust emissions, and power economy are evaluated. A production automotive engine was tested in a bench test dynamometer, with the absorption refrigeration system adapted to the exhaust pipe. The engine was tested for 25%, 50%, 75% and wide-open throttle valve. The refrigerator reached a steady state temperature between 4 and 13 °C about 3 h after system start up, depending on engine throttle valve opening. The calculated exhaust gas energy availability suggests the cooling capacity can be highly improved for a dedicated system. Exhaust hydrocarbon emissions were higher when the refrigeration system was installed in the engine exhaust, but carbon monoxide emissions were reduced, while carbon dioxide concentration remained practically unaltered.     

热水型双效压缩吸收式制冷循环热力分析

通过对太原地区中央空调运行费用的调查,得出热水型溴化锂机组运行费用相对较小。针对集中供热热水用于溴化锂吸收式制冷时的温度不匹配问题,提出在双效并联循环中增加一个加压装置的办法,通过补偿一部分电能以扩大双效循环对热源温度的适用范围,从而使得双效溴化锂吸收式制冷可以使用集中供热一次热源作为驱动能源。     

新型分布式热电冷三联供系统应用

本系统采用天然气发电机组、溴化锂机组和地源热泵机组等组成高效的热电冷三联供系统。夏季,溴化锂机组和地源热泵机组产生的冷水汇总送至用冷区域用于制冷;冬季,发电机组冷却高低温循环水通过板式换热器产生与地源热泵机组和溴化锂机组品质相同的热水,汇总送至用热区域用于采暖。本文阐述了利用燃气内燃机发电的余热,带动溴化锂机组,结合地源热泵技术,提高了能源的梯级利用,满足了用户的能量需求,同时大幅度减少能源费用支出。     

新型分布式热电冷三联供系统应用

本系统采用天然气发电机组、溴化锂机组和地源热泵机组等组成高效的热电冷三联供系统。夏季,溴化锂机组和地源热泵机组产生的冷水汇总送至用冷区域用于制冷;冬季,发电机组冷却高低温循环水通过板式换热器产生与地源热泵机组和溴化锂机组品质相同的热水,汇总送至用热区域用于采暖。本文阐述了利用燃气内燃机发电的余热,带动溴化锂机组,结合地源热泵技术,提高了能源的梯级利用,满足了用户的能量需求,同时大幅度减少能源费用支出。     

Power generation and cooling capacity enhancement of natural gas processing facilities in harsh environmental conditions through waste heat utilization

Most natural gas (NG) producers in the Persian Gulf face increasing challenges in meeting their domestic gas demands and therefore seek to reduce their NG consumption. Concurrently, the on‐site power generation and cooling capacities of local NG processing facilities are constrained by extreme climatic conditions. A combined cooling and power scheme based on gas turbine (GT) waste heat‐powered absorption refrigeration is techno‐economically assessed to reduce the NG consumption of a major gas processing plant in the Persian Gulf. The scheme utilizes double‐effect water‐lithium bromide absorption refrigeration activated by steam generated from GT exhaust gas waste heat to provide both GT compressor inlet air and process gas cooling. Based on a thermodynamic analysis, recovery of 150 MW of GT waste heat is found to enhance the plant cooling capacity by 195 MW, thereby permitting elimination of a 32.6 MW GT and existing cooling equipment. On‐site power generation is enhanced by 196 GWh annually through GT compressor inlet air cooling, with energy efficiency (i.e., 64%) improved by 35% using cogeneration relative to the existing power generation plant. The overall net annual operating expenditure savings contributed by the combined cooling and power system are of $US13 million to 34 million based on present and projected local utility prices, with an economic payback period estimated at 2 to 5 years. These savings translate to approximately 94 to 241 MMSCM of NG per year, highlighting the potential of absorption refrigeration to both enhance the power generation and cooling capacity of hydrocarbon processing plants exposed to harsh environmental conditions and to realize substantial primary energy savings. Copyright © 2014 John Wiley & Sons, Ltd.     

Modeling and simulation of solar absorption system performance in Beirut

An analytical study is performed on solar energy utilization in space cooling of a small residential application using a solar lithium bromide absorption system. A simulation program for modeling and performance evaluation of the solar-operated absorption cycle is done for all possible climatic conditions of Beirut. The results have shown that for each ton of refrigeration it is required to have a minimum collector area of 23.3 m² with an optimal water storage tank capacity ranging from 1000 to 1500 liters for the system to operate solely on solar energy for about seven hours a day. The monthly solar fraction of total energy use in cooling is determined as a function of solar collector area and storage tank capacity.An economic assessment is performed based on current cost of conventional cooling systems. It is found that the solar cooling system is marginally competitive only when combined with domestic water heating.     

应用溴化锂吸收式制冷技术提高燃气轮机电站发电效率的研究

对燃气轮机进口的空气进行预冷,能够提高发电机组的输出功率。与蓄冷方法相比,使用燃气轮机－蒸汽联合循环电站余热锅炉低压蒸发器的一部分蒸汽为热源,利用溴化锂吸收式制冷机制取冷源,冷却燃气轮机进口处的空气,以提高发电机组的输出功率,该方法技术可行,经济效益显著。     

Experimental investigation of integrated refrigeration system (IRS) with gas engine,compression chiller and absorption chiller

An integrated refrigeration system (IRS) with a gas engine, a vapor-compression chiller and an absorption chiller is set up and tested. The vapor-compression refrigeration cycle is operated directly by the gas engine. The waste heat from the gas engine operates the absorption refrigeration cycle, which provides additional cooling. The performance of the IRS is described. The cooling capacity of the IRS is about 596 kW, and primary energy ratio (PER) reaches 1.84 at air-conditioning rated conditions. The refrigerating capacity of the prototype increased and PER of prototype decreased with the increase of the gas engine speed. The gas engine speed was preferably regulated at part load condition in order to operate the prototype at high-energy efficiency. The refrigerating capacity and PER of the prototype increased with the increase of the outlet temperature of chilled water or the decrease of the inlet temperature of cooling water. The integrated refrigeration chiller in this work saves running costs as compared to the conventional refrigeration system by using the waste heat.     

Thermodynamic performance analysis of gas-fired air-cooled adiabatic absorption refrigeration systems

In China, the application of small size gas-fired air-cooled absorption refrigeration systems as an alternative for electric compression air conditioning systems has shown broad prospects due to occurrence of electricity peak demand in Chinese big cities and lack of water resources. However, for conventional air-cooled absorption refrigeration systems, it is difficult to enhance the heat and mass transfer process in the falling film absorber, and may cause problems, for example, remarkable increase of pressure, temperature and concentration in the generators, risk of crystallization, acceleration of corrosion, degradation of performance, and so on. This paper presents a gas-fired air-cooled adiabatic absorption refrigeration system using lithium bromide–water solutions as its working fluid, which is designed with a cooling capacity of 16 kW under standard conditions. The system has two new features of waste heat recovery of condensed water from generator and an adiabatic absorber with an air cooler. Performance simulation and characteristic analysis are crucial for the optimal control and reliability of operation in extremely hot climates. A methodology is presented to simulate thermodynamic performance of the system. The influences of outdoor air temperature on operation performances of the system are investigated.