發(fā)布時間：2018-01-16 06:13

  本文關(guān)鍵詞：半導體制冷系統(tǒng)熱力學分析及其在原漿鮮啤酒保鮮裝置中的應用研究　出處：《山東大學》2016年碩士論文　論文類型：學位論文

  更多相關(guān)文章： 熱電制冷 熱電材料 熱管 熱管散熱器 啤酒保鮮裝置

【摘要】：隨著人類認識的進步,特別是對于環(huán)境保護認識的進步,保護環(huán)境也成為目前科學技術(shù)發(fā)展所需要關(guān)注的熱點之一,科學的發(fā)展就需要與環(huán)境和諧共處,從而實現(xiàn)可持續(xù)發(fā)展。在20世紀80年代,科學家確認了氯氟烴(CFCs)是引起臭氧層破壞和溫室效應的危害物質(zhì),世界各國就開始逐步禁止其使用。傳統(tǒng)的制冷技術(shù)面臨必須尋找新的制冷工質(zhì)的挑戰(zhàn),而半導體熱電材料的發(fā)展,推動了半導體制冷技術(shù)在實際工程域中的應用,特別是民用領(lǐng)域中的應用。本文就是在這個大背景下,設計了一種新型的熱電制冷原漿鮮啤酒保鮮裝置,并對該裝置進行了實驗研究。本文首先概述了熱電理論發(fā)展歷程,以及目前國內(nèi)外熱電材料、熱電制冷技術(shù)、熱管和熱管散熱器的發(fā)展現(xiàn)狀；然后,對熱電系統(tǒng)的理想制冷循環(huán)和熱管散熱器的傳熱特性進行了分析,并且對實際制冷系統(tǒng)的熱力模型進行了無量綱化,分析了無量綱電流、無量綱優(yōu)值系數(shù)、冷熱端無量綱熱阻以及冷熱端熱媒溫度比值等參數(shù)變化對制冷性能的影響；最后,建立了基于熱電制冷系統(tǒng)的原漿鮮啤酒保鮮裝置,并對其進行了實驗研究,研究了半導體制冷片的輸入電流、熱端散熱環(huán)境溫度、冷端液體流速、熱管散熱對流方式以及導熱硅脂的應用這幾個具體的物理因素對原漿啤酒保鮮裝置制冷性能的影響。全文得到了以下結(jié)論：(1)在理想條件下對熱電系統(tǒng)進行熱力學分析,可知系統(tǒng)的工作電流、冷熱端溫差、優(yōu)值系數(shù)對系統(tǒng)的制冷量和制冷效率都有顯著的影響。(2)對實際熱電制冷系統(tǒng)進行無量綱熱力學分析,可知熱電制冷器存在著最佳的工作電流區(qū)域,系統(tǒng)在該電流區(qū)域中運行,可得到較好的制冷效果；熱端散熱器環(huán)境溫度對制冷性能的影響較大,改善熱端的散熱環(huán)境和散熱方式可較大幅度提高系統(tǒng)的制冷性能。(3)對熱電制冷系統(tǒng)的原漿鮮啤酒保鮮裝置進行實驗,可知保鮮裝置熱端的熱管散熱器采用自然對流時,制冷效果會惡化,無法滿足保鮮要求,而熱管翅片采用強迫對流冷卻情況下,環(huán)境溫度控制在合理范圍,工作電流在6-7A之間,保鮮裝置的制冷效果較好,啤酒桶內(nèi)液體的溫度可維持在3-5℃,滿足保鮮要求。(4)在制冷片冷熱端均勻涂上導熱硅脂,減小傳熱熱阻可以明顯提高系統(tǒng)的制冷性能。減小熱端傳熱熱阻,可使系統(tǒng)的制冷量和制冷效率有明顯的增大和提高。本文的實驗結(jié)果為熱電制冷裝置提供了優(yōu)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，

本文編號：1431875