溴化鋰吸收式冰水機的熱力學分析與熱力經濟學最適化設計

Thermodynamic Analysis and Thermoeconomic Optimization of a LiBr Absorption Chiller

林志謙(Zhi-Qian Lin)

指導教授 ： 鄭智成

國立臺北科技大學/工程學院/化學工程研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00296

摘要

本論文主要是對溴化鋰吸收式冰水機做熱力學分析與熱力經濟學最適化設計，首先在每個單元熱交換器依造不同的熱傳性質和質傳性質做質量平衡、能量平衡和其它相關方程式建立起溴化鋰吸收式冰水機的模式。在模式建立後將對吸收式冰水機做熱力學分析，分析在每個單元系統中的不可逆性(irreversibility)，並對各種不同狀態下進行模擬，探討在不同操作條件下對整個吸收式冰水系統性能係數(COP)及可用能效率( ex y )的影響。最後將對整個吸收式冰水機使用熱力經濟學的概念去設計，此方法即為結構法，結構法結合了熱力學上的考量和經濟學上的最適化，此方法的好處是能夠各別單元做最適化，不必一次考慮總系統的最適化。結構法主要是目標函數的推導配合上CSB 的使用可以得到各別單元最適化熱交換器面積，最後將使用修改型的結構法和一般型的結構法結果做比較。最適化模擬的結果顯示，整個溴化鋰吸收式冰水機的COP 和總費用都將會得到改善，而可用能效率值會隨著不同操作時間變化而得到不同值。

關鍵字

吸收式冰水機 ； 可用能 ； 熱力經濟學 ； 最適化設計 ； 結構法

並列摘要

This study presents the thermodynamic analysis and thermoeconomic optimization of a lithium bromide (LiBr) absorption chiller. The mathematical model of a LiBr absorption chiller is first established based on mass balance relations, energy balance relations, and some constitutive equations of each heat exchanger unit. Then, this study analyzes the thermodynamic properties of the absorption chiller, and calculates the irreversibility and energy loss of each unit. Simulations of the absorption chiller are carried out to investigate the effects of various operating conditions on the coefficient of performance (COP) and exergy efficiency (Ψex) of the
absorption chiller.
Moreover, this study presents the optimum design of the absorption chiller using a thermoeconomic optimization method, known as the structural method. This method not only takes the thermodynamic considerations into account but also considers their economic optimization. The advantage of using the structural method for thermoeconomic optimization is that the various elements of the system can be optimized on their own. A simple equation to calculate the optimum area of each heat exchanger can be derived by introducing the structural coefficient bond (CSB), and a
modified optimization procedure is proposed. Simulation results show that the total cost and COP are improved after the optimization, while the improvement of exergy
efficiency depends on the operation time.

並列關鍵字

absorption chiller ； exergy ； thermoeconomic ； optimization ； structural

參考文獻

[17] Ming-Tsun Ke, Absorption chiller, National Taipei University of Technology Department of Energy and Refrigerating Air-Conditioning Engineering

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