【作者】 董海虹；

【导师】 朱家玲；

【作者基本信息】 天津大学 ， 热能工程， 2006， 硕士

【摘要】 第二类吸收式热泵是回收低温位热能的有效装置之一。本文针对地热采暖中普遍存在的地热尾水排放温度较高问题,提出了利用溴化锂第二类吸收式热泵系统回收低温余热的节能方案。本文根据热力学原理,通过建立质量和能量平衡关系方程,利用工质的热物性数学关联式,建立了溴化锂第二类吸收式热泵系统的数学模型,编写了系统循环模拟软件。分析了系统主要参数蒸发温度、冷凝温度、吸收温度和发生温度等参数对系统性能的影响趋势和规律,根据分析可知,通过提高蒸发温度、降低冷凝温度和降低吸收温度的方法来提高系统的性能。本文采用约束非线性规划方法中的可变容差法,对用于回收地热余热的溴化锂第二类吸收式热泵系统进行了优化设计。在系统模拟程序的基础上,编写了优化程序。针对本文提出的节能方案,在对原有优化目标函数分析讨论的基础上,提出了新的优化目标函数1/(COP/A)(LH tA),该目标函数不但考虑了热泵系统的性价比,而且还兼顾了废热水的回收利用效果,以新目标函数对节能方案进行优化计算得到了较为理想的计算结果。在热泵系统循环模拟与优化分析的基础上,利用Visual FORTRAN与VB语言,开发出了适用于低温废热水驱动的溴化锂第二类吸收式热泵系统的模拟优化软件AOS,它的开发为复杂的优化设计工作提供了便利。应用软件AOS,对一实际别墅小区进行了供热系统的设计计算,并对此设计方案的经济性、节能性和环境效益进行了分析讨论。通过与燃油锅炉、燃气锅炉、中高温热泵以及城市集中热网等其它采暖方式进行对比分析后得出,溴化锂第二类吸收式热泵在某种特定条件下,经济性具有一定的优越性,可达到节能和环保的目的。更多还原

【Abstract】 The Absorption Heat Transformer is a kind of energy-saving equipments, which can recover effectively the low-temperature waste heat. Because there are usually lots of low-temperature waste heat discharged from the process of supplying heat in winter by the hot geothermal water, this paper proposes an energy-saving scheme using the AHT system to recovery the geothermal waste heat.Based on the thermodynamics principles, the LiBr-H2O AHT system is described mathematically by establishing the mass balance equation and the energy balance equation and utilizing the mathematical equation about the LiBr-H2O’s thermal properties. The simulation program of the LiBr-H2O AHT system is complied and through using the simulation program, the change of the LiBr-H2O AHT system’s performance on the main system parameters, the evaporating temperature, the condensing temperature, the absorbing temperature, the generating temperature and etc, is discussed. From the discussion, the system’s performance can be improved by raising the absorbing temperature, lowering the condensing temperature or lowering the condensing temperature. The optimization designing of the LiBr-H2O AHT system is analyzed by using the variable tolerance method, one of the nonlinear programming methods. On the basis of the simulation program, the optimization program is complied. In accordance with the energy-saving scheme’s characteristics, a new majorized function considering both the ratio of quality to price and the waste heat recovering effect, was proposed through analyzing the optimization results under the old majorized functions and a perfect optimum design result is obtained by utilizing the optimization program under the new majorized function. A new software, AOS, is developed by applying FORTRAN and VB, which is applicable for the optimization designing of the LiBr-H2O AHT system for recovering the heat of low-temperature waste water and it simplifies the complicated optimization designing. The optimum design of an actual villa district is completed by using the AOS software and the economical efficiency, energy-saving efficiency and environment efficiency are discussed. The results of discussion show, the economical efficiency, energy-saving efficiency and environment efficiency of the LiBr-H2O AHT system is excellent under certain conditions, contrasting to the oil-fired boiler, the gas-fired boiler, medium-high temperature heat pump and the city heating net.更多还原