【作者】 黄涛；

【导师】 雷飞；

【作者基本信息】 华中科技大学 ， 建筑与土木工程， 2021， 硕士

【摘要】 直燃型溴化锂空调系统是我国常用的空调系统形式之一。随着运行年限的增长,该形式制冷机的制冷量衰减十分明显,且大多数系统在运行过程中并没有做节能优化,导致能耗逐渐升高,房间的热舒适性也逐渐变差。为了解决直燃型溴化锂机组制冷量衰减、提高运行效率问题,本文针对直燃型溴化锂空调系统的常见问题提出了几种不同改造及运行优化方案。同时,基于TRNSYS仿真软件分别建立了原系统、改造系统仿真模型,并通过仿真模拟对比,初步解决了直燃型溴化锂机组由于性能衰减导致房间热舒适性差及空调系统的运行能耗增加的问题。本文以武汉某办公建筑直燃型溴化锂空调系统为研究对象,基于现场调研及实际测量,分析了该系统直燃型溴化锂机组的制冷/制热量的衰减情况。同时,本文采用厂家提供的样本数据,通过多项式拟合的方法,建立了直燃型溴化锂机组的数学模型,并基于数学模型在TRNSYS软件上开发了对应的机组模块。并利用该模块搭建了建筑原空调系统的仿真模型,通过对原空调系统的模拟分析,发现原空调系统可以满足冬季的空调房间热舒适性需求,但夏季的空调房间热舒适性较差。为了解决机组制冷量衰减导致房间热舒适性差的问题,本文提出了两种改造路线。通过仿真模拟,从系统能耗、经济性、环境效益等方面对比分析不同的改造方案效果,最终得出最佳改造方案:采用增加空气源热泵弥补原系统溴化锂机组制冷量的不足。针对直燃型溴化锂空调系统的运行优化问题,本文提出了水泵变频以及变冷冻水供水温度的运行优化方案。当水泵变频运行时,水泵节能率为60.28%,系统全年能耗降低了10.23%,SCOP提高了11.39%。当采用变冷冻水供水温度运行时,最佳变冷冻水温度运行方案为基于系统部分负荷率的变化调整冷冻水供水温度。相对于系统运行优化前,优化后的系统全年节能率为11.73%,SCOP提高了13.29%。更多还原

【Abstract】 Direct-fired lithium bromide(Li-Br)air-conditioning system is one of the commonly used forms of air-conditioning systems in China.As the working years of the system increase,the cooling capacity of this type of refrigerator has attenuated significantly,and most systems are not optimized for energy saving during operation,resulting in a gradual increase in energy consumption and a gradual deterioration in the thermal comfort of the room.In order to solve the problem of attenuation of cooling capacity of direct-fired Li-Br units and improve operating efficiency,this thesis proposed several different transformation and operation optimization schemes for the common problems of direct-fired Li-Br air conditioning systems.At the same time,based on the TRNSYS simulation software,the original system and the modified system simulation models were established.Through simulation comparison,the problem of poor thermal comfort in the room and increased operating energy consumption of the air conditioning system due to performance degradation of the direct-fired Li-Br unit were initially solved.An office building equipped with the direct-fired Li-Br air conditioning system in Wuhan was selected in this thesis as the research objective.Based on on-site investigation and actual measurement,the cooling/heating attenuation of the direct-fired Li-Br unit of the system was analyzed.At the same time,this article used the sample data provided by the manufacturer to establish the mathematical model of the direct-fired Li-Br unit through the polynomial fitting method.Then the corresponding unit module on the TRNSYS software based on the mathematical model was developed.And this module was used to build a simulation model of the original air-conditioning system of the building.Through the simulation analysis of the original air-conditioning system,it was found that the original air-conditioning system can meet the thermal comfort requirements of air-conditioned rooms in winter,but the thermal comfort of air-conditioned rooms in summer is poor.In order to solve the problem of poor room thermal comfort caused by the attenuation of unit cooling capacity,this thesis proposed two transformation routes.Through simulation,comparing and analyzing the effects of different retrofit schemes in terms of system energy consumption,economy,and environmental benefits,the best retrofit scheme was finally reached by the usage of additional air source heat pumps to make up for the lack of cooling capacity of the original system Li-Br unit.Aiming at the operation optimization problem of the direct-fired Li-Br air-conditioning system,this thesis proposed an operation optimization scheme by the variable-frequency control of the water pump and the variable supply chilled water temperature control of the Li-Br units.When the water pump was running with variable frequency,the energy saving rate of the water pump is 60.28%,the annual energy consumption of the system is reduced by 10.23%,and the SCOP is increased by 11.39%.When operating with variable chilled water temperature,the best variable chilled water temperature operating program was achieved by adjusting the chilled water supply temperature based on the change in the system’s partial load rate.Compared with the system before optimization,the optimized system has an annual energy saving rate of11.73%,and SCOP has increased by 13.29%.更多还原