不可逆铁电斯特林制冷循环性能的优化

发布时间：2018-05-07 01:06

本文选题：斯特林制冷机 + 铁电晶体材料　；参考：《河北科技大学》2014年硕士论文

【摘要】：当今制冷技术已广泛应用于许多领域，如国防通讯、生活起居、工作环境、等等，为了更加贴近实际，许多学者开始从有限时间热力学的角度来研究制冷系统。同时，随着科学技术的发展，温室效应问题也日趋严重。为了解决这些矛盾，固体制冷引起人们的注意，其中的铁电晶体斯特林制冷机以其高效率、低噪音、环保和便于维护等优点而备受推崇得到了越来越多科技工作者的关注。近几年来，许多有关铁电制冷材料、铁电制冷样机和铁电制冷循环理论等研究已成为热门研究课题。围绕制冷循环中实际存在的各种不可逆因素，学者们已经分析计算出一到两种不可逆因素对制冷循环性能的影响。本论文将在这些研究成果的基础上开展铁电斯特林制冷循环性能的研究，分析多种不可逆因素并存时对铁电斯特林制冷循环的影响，，用最优控制理论方法优化性能参量，从而提高系统的整体性能。所建立的模型更加贴近实际，获得的理论具有更大的普遍性，而且有极大的实用价值。第一章简要介绍有限时间热力学的产生和发展现状。阐述了铁电晶体的基本特性原理及制冷优势。第二章建立不可逆铁电斯特林制冷循环循环新模型，在铁电晶体的热力学性质基础，利用有限时间热力学、最优控制理论，推导出制冷率、制冷系数的数学表达式，并以制冷系数为目标函数对循环的制冷率进行优化分析。应用数值计算获得制冷率制冷系数的性能曲线，并分析其优化工作区域。第三章继续深入推导有限速率热传导、回热损失、热漏损失、和工质内不可逆性等因素对铁电斯特林制冷循环影响，数值计算和图解法详细讨论了这些不可逆因素对制冷循环的影响程度，获得了输入功率、极限制冷温度、等温时间比等重要性能参量数学表式及相关界限。文章最后对几种特殊情况作了分析讨论，得出了与文献中一致的理论。本论文所得结论可以作为进一步深入研究铁电斯特林制冷循环系统性能特性的理论基础，也可以对铁电晶体斯特林制冷机的参数优化设计、性能改善有所帮助。
[Abstract]:Nowadays, refrigeration technology has been widely used in many fields, such as national defense communication, daily life, working environment, and so on. In order to get closer to reality, many scholars have begun to study refrigeration system from the point of view of finite time thermodynamics. At the same time, with the development of science and technology, Greenhouse Effect problem is becoming more and more serious. In order to solve these problems, solid state refrigeration has attracted people's attention. The ferroelectric crystal Stirling refrigerator has been paid more and more attention by more and more scientists because of its high efficiency, low noise, environmental protection and easy maintenance. In recent years, many researches on ferroelectric refrigeration materials, ferroelectric refrigeration prototypes and ferroelectric refrigeration cycle theory have become a hot research topic. Focusing on the actual existence of various irreversible factors in the refrigeration cycle, scholars have analyzed and calculated the influence of one or two irreversible factors on the performance of the refrigeration cycle. On the basis of these research results, this paper will study the performance of ferroelectric Stirling refrigeration cycle, analyze the influence of many irreversible factors on the ferroelectric Stirling refrigeration cycle, and optimize the performance parameters with the optimal control theory. In order to improve the overall performance of the system. The established model is closer to reality, and the obtained theory is more universal and of great practical value. The first chapter briefly introduces the generation and development of finite time thermodynamics. The basic characteristic principle and refrigeration advantage of ferroelectric crystal are described. In the second chapter, a new model of irreversible ferroelectric Stirling refrigeration cycle is established. Based on the thermodynamic properties of ferroelectric crystals, the mathematical expressions of refrigeration rate and refrigeration coefficient are derived by using finite time thermodynamics and optimal control theory. The refrigeration rate of the cycle is optimized and analyzed with the refrigeration coefficient as the objective function. The performance curve of refrigeration coefficient was obtained by numerical calculation, and the optimum working area was analyzed. In chapter 3, the influence of finite rate heat conduction, heat recovery loss, heat leakage loss, and irreversibility of refrigerant on the ferroelectric Stirling refrigeration cycle is derived. The influence of these irreversible factors on the refrigeration cycle is discussed in detail by numerical calculation and graphical method. The mathematical expressions and relevant bounds of important performance parameters, such as input power, limit refrigeration temperature and isothermal time ratio, are obtained. At the end of this paper, several special cases are analyzed and discussed, and the theory which is consistent with the literature is obtained. The conclusions obtained in this paper can be used as the theoretical basis for further research on the performance characteristics of ferroelectric Stirling refrigeration cycle, and can also be helpful to the optimization design of the parameters of the ferroelectric Stirling refrigerator and the improvement of its performance.
【学位授予单位】：河北科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB651

【参考文献】