吸收式制冷循环特性的稳态模拟

对溴化锂水溶液的热力性质进行模拟,得到较为精确的确定溴化锂水溶液热力参数的计算方法,为溴化锂吸收式制冷循环系统的模拟奠定基础。编制吸收式制冷机组循环模拟程序,对溴化锂吸收式制冷循环的单效及双效并联进行模拟,通过对比试验数据与模拟结果,发现模拟能够取得较为理想的结果。     

溴化锂吸收式热泵循环理论分析与计算机模拟

以溴化锂水溶液的热物性参数计算公式和美国供暖制冷空调工程协会（ASHRAE）给出的溴化锂水溶液的平衡方程为基础,通过模拟计算得到了较为精确的确定溴化锂水溶液热物性参数的计算方法。进而对单效热泵循环的仿真模拟计算,实现了对机组在不同工况下的性能预测。为实验研究提供了分析方法,为企业生产提供了设计思路。     

塑料换热技术在溴化锂吸收式制冷机上的应用展望

溴化锂吸收式制冷机在工业中有着广泛的应用,但换热装置腐蚀及其引起的冷量衰减一直以来是人们难以解决的问题.根据现有的溴化锂吸收式制冷机组的性能,结合塑料换热装置的一些特点,提出了采用塑料换热装置代替金属换热装置来解决溴化锂吸收式制冷机的这个难题;并以研制一台制冷量为3.49×104W的溴化锂吸收式制冷机组为例,对塑料换热装置的溴化锂吸收式制冷机组与传统金属溴化锂吸收式制冷机组相关部件的参数进行比较.通过对溴化锂吸收式制冷机组的传热面积、管道阻力的计算和安全强度的校核,发现塑料换热装置应用在溴化锂吸收式制冷机上是可行的,塑料换热技术在溴化锂吸收式制冷机上有着较好的应用前景.     

塑料管单效溴化锂吸收式制冷机理论与实验研究

溴化锂吸收式制冷机在工业中有着广泛的应用,但传热管腐蚀及其引起的拎量衰减一直以来是人们难以解决的问题。采用塑料传热管代替铜传热管有望解决这个难题。分析了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,设计了塑料管单效溴化锂吸收式制冷机的结构,为塑料管单效溴化锂吸收式制冷机的实验性能测试提供参考依据。     

小型无泵循环溴化锂吸收式空调机的开发与研究

一、前言 1945年,美国Carrier公司制成了第一台以水为制冷剂、以溴化锂水溶液为吸收剂的吸收式制冷机。由于溴化锂吸收式制冷机具有以热能为动力、运动部件少等显著特点,正受到日益广泛的重视,并获得了迅速发展。目前,溴化锂吸收式制冷机广泛应用于石油、化工、冶金、纺织和制药等工业部门以及宾馆、电影院和办公大楼等建筑物的中央空调系统。不过,现有的溴化锂吸收式制冷机多为大型机组,小型机还不多见。美国阿克拉公司及日本矢崎总业     

溴化锂吸收式制冷循环的计算与分析

本文通过对国产溴化锂水溶液物性的实测数据进行回归分析,提出了溴化锂水溶液的平衡方程和焓-浓度方程。进而介绍了利用这两个方程在电子计算机上进行溴化锂吸收式制冷循环热力计算的方法。计算表明,采用上述方法较之查图表手算,既迅速又准确。文中还分析了吸收式制冷机所适用的热源温度。     

溴化锂机组冷却炼厂循环水的应用分析

炼厂低温余热由于温度低、热源分布广等特点,回收热能困难,回收低温余热成为我国炼油企业节能的重要途径之一.本文通过对溴化锂吸收式制冷及炼厂低温热特点的分析,提出利用低温热作为驱动溴化锂吸收式制冷机的热源的方案,并以某催化裂化装置为例,设计单效溴化锂吸收式制冷机.该制冷机设计合理,COP为0.67,产生的冷量为8.8741 x10 7kcal/h,可实现年节省2050.3万元,经济效益显著.低温余热驱动溴化锂吸收式制冷机可以完全冷却本装置产生的循环水,实现炼厂的节能减排目标,而该制冷机安全环保,应用于炼厂的低温热回收安全可靠.     

三效溴化锂吸收式制冷机概述

溴化锂吸收式制冷机是以热能为动力,水为制冷剂,溴化锂水溶液为吸收剂制取空调或工艺用冷(热)水的制冷设备。这种制冷机因为热能为动力,能源利用的范围广,特别是余热、废热、排热的利用使溴化锂吸收式制冷机具要节能的特性。同时,因为水为制冷工     

一种新的轿车空调方案——单效溴化锂吸收式冷热水机组

为了减少轿车的油耗和提高轿车的动力性，本文应用热力学和传热学的方法，通过对现有轿车空调系统和单效溴化锂吸收式冷热水机组轿车空调系统的分析比较，指出利用发动机高温冷却液驱动的单效溴化锂吸收式冷热水机组代替现有空调系统的可行性。并对轿车空调用单效溴化锂吸收式冷热水机组工作原理进行了简要说明。     

太阳能与天然气综合供热的小型吸收式制冷机在别墅建筑的应用

本文通过对一别墅建筑用小型太阳能及天然气为热源的单效吸收式空调系统的组成分析和吸收式制冷机组模型的热力计算,为太阳能在别墅建筑的推广应用提供一个理论模式.     

Supply of cooling and heating with solar assisted absorption heat pumps: an energetic approach

The primary energy consumption of two kinds of solar assisted absorption systems (solar assisted absorption chiller during summertime and heat pump during wintertime or solar assisted absorption chiller with direct gas combustion for heating during wintertime) is compared with the primary energy consumption of a compression chiller which can work as a heat pump during wintertime. For the absorption systems three technical options were considered: a single effect machine; a double effect machine with the solar energy delivered to the lower temperature desorber and combustion heat of a gas burner delivered to the higher temperature desorber; a double effect machine with both solar energy and combustion heat delivered to the higher temperature desorber. The analysis performed in this article shows that solar assisted absorption chillers, absorption heat pumps and direct solar heating systems even with low and intermediate solar fractions can operate with considerably less primary energy consumption than compression systems. Further, the necessary solar collector area to achieve that goal is compatible with roof area available in buildings. It was also verified that, for the double effect absorption machines, there is no advantage in delivering the solar energy to the higher temperature desorber, thus establishing as preferable the solution in which it is delivered to the lower temperature desorber.     

Dynamic simulation of a single-effect ammonia–water absorption chiller

A lumped-parameter dynamic simulation of a single-effect ammonia–water absorption chiller is performed. Modeling is based on the continuity of species constituting the ammonia–water mixture and the conservation of energy for each component of the absorption chiller. Ordinary differential equations governing the response of each component and the algebraic equations describing the constitutive relation are solved in parallel by numerical integration. The model has been applied to a commercially available 10.5 kW absorption chiller to study the transients of temperature, pressure, concentration, and void fraction of each component during the start-up operation. The time constant of the absorption chiller is also investigated. The parameters considered are the bulk concentration of the ammonia–water solution, the mass of the solution filled, and the volumes of key components of the absorption chiller. In addition, the reduction of the time constant by a stepwise turn-up and turn-down of the flue gas flow rate during the primary stage of start-up period is demonstrated.     

Experimental evaluation of a variable effect LiBr–water absorption chiller designed for high-efficient solar cooling system

A variable effect LiBr–water absorption chiller is studied in this paper based on a real developed 50 kW prototype. The chiller is designed specifically for the high-efficient utilization of the solar power with variable temperature. It can obtain the optimized COP and cooling power under different heat source temperatures. The construction, circulation and testing system of the chiller were introduced. A typical running condition of the chiller from the starting to the steady operating was given to show the dynamic performance. Several groups of the temperatures and COPs were given to show the steady state performance. These data showed that the COP increased from 0.69 to 1.08 under generation temperature from 95 °C to 120 °C. Besides, the effects of chilled water temperature, cooling water temperature, pump frequency and opening of valve on COP and cooling power were analyzed respectively.     

多主机制冷机房变流量解耦控制策略研究

在单主机制冷机房变流量解耦控制策略基础上,探讨了多主机制冷机房的变流量解耦控制策略。在考虑冷水机组COP值同时是冷负荷及冷却水进水温度的函数基础上,通过比较不同冷负荷分配策略对制冷机房能耗的影响,得到了在大多数负荷区间,采用均匀分配总冷负荷的策略最为节能。这说明,前期关于单主机制冷机房变流量变温差控制方式可推广至多主机制冷机房变流量控制。     

溴化锂主机冷却水水质问题分析

对一例具体工程溴化锂主体铜管腐蚀的原因进行详细实验分析，发现冷却水中产生：铜管点蚀的主要原因是冷却水中存在着Cl^-离子，但腐蚀部位的Cl^-含量却大大低于国家行业标：准中控制含量，故在此文中提出质疑。     

机械振动强化吸收式制冷机传热性能的实验研究

本文搭建了带有电动振动系统的吸收式制冷性能研究实验台,实验重点研究了振动对于吸收式制冷机传热性能的强化效果。结果表明,振动可有效地强化吸收式制冷机的传热性能,增加制冷量;在低频、低振幅的范围内,传热的强化效果随频率和振幅的增加而增加。本文的研究成果对于提高溴化锂吸收式制冷机的效率有一定的借鉴作用。     

New absorption chiller and control strategy for the solar assisted cooling system at the German federal environment agency

Typically the cooling capacity of absorption chillers is controlled by adjusting the driving hot water temperature according to the load. Meanwhile the cooling water temperature is controlled to a constant set value. In order to increase the solar cooling fraction and/or to decrease the operating costs of solar assisted cooling systems (SAC-systems) a new control strategy has been developed which controls hot and cooling water temperature simultaneously. Hereby the specific cost of cold – generated from solar or conventional heat – can be reduced. The basic concept of the strategy is explained and results are shown for the SAC-system at the Federal Environment Agency in Dessau, Germany. Here a recently developed absorption chiller is now used instead of a former adsorption chiller. With the new absorption chiller and the control strategy the seasonal energy efficiency ratio SEER is above 0.75, electric efficiency is 35% higher and water consumption is reduced by 70%.     

提高蒸汽型溴化锂吸收式制冷机制冷性能的管理方法

根据对冷水站蒸汽型溴化锂吸收式制冷机的长期管理,提出了在气密性、溴化锂溶液、冷剂水、冷水及冷却水的水质、运行、设备等方面进行优化管理的方法,它不仅保证了制冷机组的长期稳定运行,而且提高了制冷机组的制冷性能。     

上海某建筑中央空调机组的优化运行方案

研究离心式冷水机组与直燃型溴化锂吸收式机组的运行方案,通过比较其总运行费用、折算一次能源总耗量和总耗钱效率,确定优先开满离心机组,配合使用溴化锂机组的设计方案是可行的,节能效果明显。