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热膨胀系数随温度变化对微管固体氧化物燃料电池残余应力的影响

时间:2023-01-15 20:01来源:毕业论文
热膨胀系数随温度变化对微管固体氧化物燃料电池残余应力的影响。对比分析了热膨胀系数随温度变化与热膨胀系数为定值的两种状况对结果的影响。发现层厚度增加使本层残余应力减

摘 要目前随着社会发展,人类日益增长的物质需求与日趋枯竭的化石能源、破坏严重的生态环境之间的矛盾愈加凸显,新能源的开发与利用成为一个炙手可热的话题。在诸多新能源技术中,燃料电池作为一种新型的发电技术,以其高效、环保、安全、适应性强的特点,备受人们青睐。而固体氧化物燃料电池(SOFC)性能较之其它尤显优异。微管式固体氧化物燃料电池(MT-SOFC)具有体积功率密度较大、升降温速率高、机械性能更强、便携性和移动性好等诸多优势,是燃料电池领域的最新研究成果。然而其在烧结过程中受温度变化及各层热膨胀系数差异影响,会产生较高残余应力,损伤几率过高。本文主要研究了热膨胀系数随温度变化对微管固体氧化物燃料电池残余应力的影响。87043

第一章介绍了燃料电池背景、工作原理、种类及特点、发展历史等基础知识,着重介绍了固体氧化物燃料电池(SOFC)的特点、结构形式以及其研究现状

第二章建立了热膨胀系数随温度变化与不随温度变化的两个MT-SOFC模型,详细介绍了建模的过程。

第三章基于第二章所建立的MT-SOFC二维轴对称模型,分析了阳极厚度变化、电解质厚度变化对各层残余应力的影响,并对比分析了热膨胀系数随温度变化与热膨胀系数为定值的两种状况对结果的影响。发现层厚度增加使本层残余应力减小,相邻层残余应力增大,考虑热膨胀系数变化比不考虑其变化计算所得结果小。

第四章分析了阳极厚度变化、电解质厚度变化对各层损伤几率的影响,探究每一种电解质厚度下阳极的理想厚度,并对比分析了热膨胀系数随温度变化与热膨胀系数为定值的两种状况对结果的影响。发现阳极厚度增大会使损伤几率减小,电解质厚度增大会使损伤几率增加,考虑热膨胀系数变化比不考虑其变化计算所得结果小。

结论部分对全文进行了总结。

毕业论文关键词:MT-SOFC,热膨胀系数,残余应力,损伤几率

Abstract Recently, with the development of society, the growing human demand for the material and increasing depletion of fossil energy, failure serious ecological environment between the contradictions become more prominent, the development and utilization of new energy is becoming a hot topic。In many new energy technologies, fuel cell as a new type of power generation technology, with its high efficiency, environmental protection, safety, strong adaptability characteristics, has been favored by people。And the performance of the solid oxide fuel cell (SOFC) is better than the others。Micro tubular solid oxide fuel cell (MT-SOFC) has many advantages, such as high mass transfer efficiency, large volume power density, high temperature, high mechanical property, good portability and mobility,is the latest research results in the field of fuel cell。However, it is affected by the temperature change and the difference of thermal expansion coefficient of each layer in the sintering process, which can produce high residual stress and have a certain damage probability。 In this paper, the effect of thermal expansion coefficient versus temperature on the residual stress of micro - solid oxide fuel cell was studied。

The first chapter introduces the background, working principle, types and the basic knowledge of the development of the fuel cell, the characteristics and structure of solid oxide fuel cell (SOFC) and its research status are introduced。

In the second chapter, the two MT-SOFC models of the coefficient of thermal expansion with temperature change and temperature does not change are established based on multiphsics5。0 COMSOL software。The process of modeling is introduced in detail。

In the third chapter, based on the MT-SOFC 2D axial symmetry model In the second chapter, to analyze the influences of anode thickness and electrolyte thickness on the residual stress of each layer, and the effects of thermal expansion coefficient with temperature change and thermal expansion coefficient on the results of two kinds of conditions。It is found that the maximum stress decreases with the increase of layer thickness, the maximum stress of the adjacent layer increases, and the change ratio of thermal expansion coefficient is smaller than that of the calculation。 热膨胀系数随温度变化对微管固体氧化物燃料电池残余应力的影响:http://www.youerw.com/wuli/lunwen_123977.html

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