半导体制冷系统热力学分析及其在原浆鲜啤酒保鲜装置中的应用研究

发布时间：2018-01-16 06:13

  本文关键词：半导体制冷系统热力学分析及其在原浆鲜啤酒保鲜装置中的应用研究　出处：《山东大学》2016年硕士论文　论文类型：学位论文

  更多相关文章： 热电制冷 热电材料 热管 热管散热器 啤酒保鲜装置

【摘要】：随着人类认识的进步,特别是对于环境保护认识的进步,保护环境也成为目前科学技术发展所需要关注的热点之一,科学的发展就需要与环境和谐共处,从而实现可持续发展。在20世纪80年代,科学家确认了氯氟烃(CFCs)是引起臭氧层破坏和温室效应的危害物质,世界各国就开始逐步禁止其使用。传统的制冷技术面临必须寻找新的制冷工质的挑战,而半导体热电材料的发展,推动了半导体制冷技术在实际工程域中的应用,特别是民用领域中的应用。本文就是在这个大背景下,设计了一种新型的热电制冷原浆鲜啤酒保鲜装置,并对该装置进行了实验研究。本文首先概述了热电理论发展历程,以及目前国内外热电材料、热电制冷技术、热管和热管散热器的发展现状；然后,对热电系统的理想制冷循环和热管散热器的传热特性进行了分析,并且对实际制冷系统的热力模型进行了无量纲化,分析了无量纲电流、无量纲优值系数、冷热端无量纲热阻以及冷热端热媒温度比值等参数变化对制冷性能的影响；最后,建立了基于热电制冷系统的原浆鲜啤酒保鲜装置,并对其进行了实验研究,研究了半导体制冷片的输入电流、热端散热环境温度、冷端液体流速、热管散热对流方式以及导热硅脂的应用这几个具体的物理因素对原浆啤酒保鲜装置制冷性能的影响。全文得到了以下结论：(1)在理想条件下对热电系统进行热力学分析,可知系统的工作电流、冷热端温差、优值系数对系统的制冷量和制冷效率都有显著的影响。(2)对实际热电制冷系统进行无量纲热力学分析,可知热电制冷器存在着最佳的工作电流区域,系统在该电流区域中运行,可得到较好的制冷效果；热端散热器环境温度对制冷性能的影响较大,改善热端的散热环境和散热方式可较大幅度提高系统的制冷性能。(3)对热电制冷系统的原浆鲜啤酒保鲜装置进行实验,可知保鲜装置热端的热管散热器采用自然对流时,制冷效果会恶化,无法满足保鲜要求,而热管翅片采用强迫对流冷却情况下,环境温度控制在合理范围,工作电流在6-7A之间,保鲜装置的制冷效果较好,啤酒桶内液体的温度可维持在3-5℃,满足保鲜要求。(4)在制冷片冷热端均匀涂上导热硅脂,减小传热热阻可以明显提高系统的制冷性能。减小热端传热热阻,可使系统的制冷量和制冷效率有明显的增大和提高。本文的实验结果为热电制冷装置提供了优化方向。
[Abstract]:With the progress of human understanding, especially for environmental protection, environmental protection has become one of the hot spots in the development of science and technology. The development of science and technology needs to coexist harmoniously with the environment. In 1980s, scientists identified chlorofluorocarbons (CFCs) as harmful substances that cause ozone depletion and Greenhouse Effect. The traditional refrigeration technology is faced with the challenge of finding new refrigerants, and the development of semiconductor thermoelectric materials. The application of semiconductor refrigeration technology in practical engineering domain, especially in the field of civil applications, is promoted. In this context, a new thermoelectric refrigeration raw pulp fresh beer preservation device is designed in this paper. Firstly, the development of thermoelectric theory, thermoelectric materials, thermoelectric refrigeration technology, heat pipe and heat pipe radiator at home and abroad are summarized. Then, the heat transfer characteristics of the ideal refrigeration cycle and the heat pipe radiator of the thermoelectric system are analyzed, and the dimensionless thermal model of the actual refrigeration system is analyzed, and the dimensionless current is analyzed. The influence of the parameters such as dimensionless optimum coefficient, dimensionless thermal resistance of the cold and hot end and the ratio of the temperature of the hot and cold side to the refrigerant temperature on the refrigeration performance; Finally, the raw pulp fresh beer fresh-keeping device based on thermoelectric refrigeration system was established, and its experimental study was carried out. The input current of semiconductor refrigeration film, the heat dissipation environment temperature at the hot end and the liquid flow rate at the cold end were studied. The influence of several physical factors on the Refrigeration performance of the Raw Pulp Beer Fresh-keeping device by Heat Pipe Heat convection method and the Application of Heat conduction Silicon Fat. The following conclusions are obtained in this paper: 1). Thermodynamics analysis of thermoelectric system is carried out under ideal conditions. It can be seen that the working current of the system, the temperature difference between the cold and hot ends, and the optimum coefficient have a significant effect on the cooling capacity and refrigeration efficiency of the system. (2) the dimensionless thermodynamic analysis of the actual thermoelectric refrigeration system is carried out. It is known that the thermoelectric cooler has the best working current area, and the system can be operated in the current region, which can get a better refrigeration effect. The ambient temperature of the hot end radiator has a great influence on the refrigeration performance. To improve the heat dissipation environment and heat dissipation mode of the hot end, the refrigeration performance of the system can be greatly improved.) the experiment on the raw pulp fresh beer fresh-keeping device of the thermoelectric refrigeration system is carried out. When the heat pipe radiator of the hot end of the preservation device adopts natural convection, the refrigeration effect will deteriorate and can not meet the requirements of preservation, and the ambient temperature will be controlled in a reasonable range under the condition of forced convection cooling of the heat pipe fin. The working current is between 6-7A and the cooling effect of the device is better. The temperature of the liquid in the beer barrel can be maintained at 3-5 鈩，

本文编号：1431875