本文選題：噴射制冷系統(tǒng) + 性能優(yōu)化��； 參考：《廣西大學(xué)》2017年碩士論文

【摘要】：隨著能源緊張及環(huán)境污染等問(wèn)題的日益突出,從節(jié)能的角度去提高能源利用率,進(jìn)而改善用能環(huán)境顯得越發(fā)重要。在噴射制冷系統(tǒng)、真空裝置、化工生產(chǎn)中噴射器均有較為廣泛的應(yīng)用。通過(guò)采用不可逆熱力學(xué)中熵產(chǎn)分析和(火用)分析的原理,將噴射器應(yīng)用領(lǐng)域拓展到制冷系統(tǒng)的實(shí)際不可逆循環(huán)過(guò)程,如傳熱、傳質(zhì)、擴(kuò)散等。本文基于熱力學(xué)理論對(duì)雙級(jí)噴射制冷系統(tǒng)的不可逆性損失進(jìn)行了深入研究,依靠動(dòng)量、質(zhì)量和能量守恒方程,推導(dǎo)出雙級(jí)噴射制冷系統(tǒng)的熵平衡及熵產(chǎn)方程,分析了其內(nèi)部流體流動(dòng)過(guò)程各個(gè)部件的熵產(chǎn)和(火用)損失的分部情況。熵能夠用來(lái)描述自然界各種運(yùn)動(dòng)形式轉(zhuǎn)化的數(shù)量、方向和不可逆性。本文在分析熱力學(xué)第一、第二定律的基礎(chǔ)上,重點(diǎn)研究了兩級(jí)串聯(lián)式噴射制冷系統(tǒng)的研究與進(jìn)展,著重介紹了熵分析方法在噴射器中的發(fā)展趨勢(shì)和應(yīng)用前景,并對(duì)比了在不同的發(fā)生溫度、蒸發(fā)溫度和冷凝溫度下,運(yùn)用不同制冷劑時(shí)制冷系統(tǒng)的噴射系數(shù)、性能系數(shù)以及機(jī)械性能系數(shù)的變化趨勢(shì)。分析了噴射制冷系統(tǒng)各部件不可逆損失的分布規(guī)律,同時(shí)也分析了操作參數(shù)變化對(duì)系統(tǒng)各部件熵產(chǎn)的影響情況,進(jìn)而能夠準(zhǔn)確地確定出使系統(tǒng)性能系數(shù)較佳同時(shí)滿足總熵產(chǎn)最小的運(yùn)行參數(shù),即系統(tǒng)工作性能最優(yōu)的工況。熱力學(xué)系統(tǒng)涉及熱量和能量的轉(zhuǎn)換過(guò)程,基于熱力學(xué)系統(tǒng)中的熵產(chǎn)及?損失分析法在噴射制冷系統(tǒng)中的應(yīng)用已逐漸被國(guó)內(nèi)外一些學(xué)者所研究。與利用熱力學(xué)第一定律中的三大守恒方程(質(zhì)量、能量、動(dòng)量守恒)的傳統(tǒng)設(shè)計(jì)方法相比,這種方法的提出在噴射制冷系統(tǒng)中各個(gè)部件能量損耗上的分析更為客觀全面。掌握噴射制冷技術(shù)的研究方法并進(jìn)行理論分析,有助于推動(dòng)噴射制冷領(lǐng)域新技術(shù)的發(fā)展,為其走向更廣泛的實(shí)用化奠定了堅(jiān)實(shí)的理論基礎(chǔ)。如何選用合適的制冷劑是改善雙級(jí)噴射制冷系統(tǒng)性能的有效手段,隨著能源的過(guò)度消耗及日益短缺問(wèn)題逐漸引起人們的重視,利用低品位熱源作為動(dòng)力驅(qū)動(dòng)的噴射制冷方式,將會(huì)得到進(jìn)一步的研究及應(yīng)用,本文的相關(guān)研究為雙級(jí)噴射制冷系統(tǒng)的性能最優(yōu)化指明了方向。
[Abstract]:With the problems of energy shortage and environmental pollution becoming more and more prominent, it is more and more important to improve the energy efficiency from the point of view of energy saving, and then to improve the environment of energy use. The ejector is widely used in ejector refrigeration system, vacuum device and chemical industry. By using the principles of entropy production analysis and exergy analysis in irreversible thermodynamics, the application of ejector is extended to the actual irreversible cycle process of refrigeration system, such as heat transfer, mass transfer, diffusion and so on. Based on the thermodynamic theory, the irreversibility loss of two-stage ejector refrigeration system is studied in this paper. Based on the conservation equations of momentum, mass and energy, the entropy equilibrium and entropy production equations of two-stage jet refrigeration system are derived. The entropy production and exergy loss of each component in the internal fluid flow process are analyzed. Entropy can be used to describe the quantity, direction and irreversibility of the transformation of various forms of motion in nature. Based on the analysis of the first and second laws of thermodynamics, this paper focuses on the research and development of two-stage series ejector refrigeration system, and emphatically introduces the development trend and application prospect of entropy analysis method in ejector. The variation trends of ejection coefficient, performance coefficient and mechanical performance coefficient of refrigeration system with different refrigerants were compared at different temperature, evaporation temperature and condensation temperature. The distribution law of irreversible loss of each component of the ejector refrigeration system is analyzed, and the influence of the operating parameters on the entropy production of each component of the system is also analyzed. Furthermore, it is possible to accurately determine the operating parameters which make the system performance coefficient better and satisfy the minimum total entropy production, that is, the optimal operating condition of the system performance. Thermodynamic systems involve the conversion of heat and energy, based on entropy production and? The application of loss analysis in ejector refrigeration system has been studied by some scholars at home and abroad. Compared with the traditional design method using the three conservation equations (mass, energy, momentum conservation) of the first law of thermodynamics, the proposed method is more objective and comprehensive in the analysis of the energy loss of each component in the ejector refrigeration system. Mastering the research methods and theoretical analysis of jet refrigeration technology will help to promote the development of new technology in the field of jet refrigeration and lay a solid theoretical foundation for its wider application. How to select suitable refrigerant is an effective means to improve the performance of two-stage ejector refrigeration system. With the excessive consumption of energy and the increasing shortage of energy, people pay more and more attention to the use of low-grade heat source as a power-driven jet refrigeration method. Further research and application will be carried out. The research in this paper points out the direction of performance optimization of two-stage ejector refrigeration system.
【學(xué)位授予單位】：廣西大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TB657

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 沈冰潔;陶樂(lè)仁;王超;虞中e，

本文編號(hào)：1981855