低品位热源驱动的libr吸收式制冷机组仿真优化-制冷及低温工程专业毕业论文.docx

山东建筑大学硕士学位论文
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Simulation Optimization ofAbsorption Refrigeration System with
Lithium-Bromide Driven by Low Grade Heat Source
Liu Yanlong(Refrigeration and Cryogenic Engineering)
Directed by Wang Qiang ABSTRANCT
Energy crisis and environmental problems have been highlighted in recent years,which
lead to the、7I,ide concern on absorption chiller driven by low grade the low thermal coefficient and large unit volume limit its large—scale application,SO it is essential for the optimization study of absorption this paper,putting the single effect LiBr absorption chiller as the research obj ect,the working fluid,refrigeration system,and
operating parameters has been studied,in which optimization and exergy analysis method was
used.
Through the theory analysis of heat and mass transfer,the mathematical and physical
modal for single effect lithium bromide absorption chiller are select
RTL method and the convergence method of limited wegstein as the basic operation
method;
The physical properties of lithium bromide-water working fluid with nitrate lithium as additives are was found that the viscosity of is reduced,and the crystallization has been significanfly solved after the additive is added,while the system performance parameters (thermal coefficient,circular ratio)get greatly analysis parison,the optimum molar ratio ofbromide lithium nitrate is 4:1,the driving heat source temperature is
lower,which demonstrate it is better suited to the absorption chiller driven by low grade heat
source;
The optimization of refrigeration system was carried out by using Aspen Plus,which
analysed the influence on the performance of the system by solution heat exchanger,series form of cooling water and dilute solution optimum range of hot。outlet and temperature approach is 7—1 5"C;The optimum form of cooling water is series form l(absorber to condenser),if the cooling water temperature is lo