摘要固体氧化物燃料电池(SOFC)经过了多年发展,相比以前性能已经有了巨大提升。电极的各种性能对SOFC的整体性能起着十分关键的作用,所以研究电极的有效性质成为了非常重要的课题,尤其是对有效电导率和有效扩散系数的研究。86186
第一章绪论内容首先介绍了当前世界上的能源现状以及燃料电池的研究背景,接着介绍了燃料电池的原理、组成和优缺点,然后着重介绍了固体氧化物燃料电池的电极发展史和电极的组成。
第二章的主要内容为模型的建立。首先介绍了建立模型所使用的EDEM软件,然后将SOFC的电极模型看成为球颗粒堆积而成,接着利用EDEM软件进行了不同尺寸模型的建立,本文根据堆积颗粒的不同一共建立了三种模型。
第三章的主要内容为对模型的处理。在处理模型的过程中本文采取了一种用点来代替堆积颗粒的思想。首先通过MATLAB软件对模型进行等价处理,然后将模型重新导入COMSOL软件,使之能够进行有效性质的计算分析。
第四章的主要内容为对模型一的计算和分析。首先根据模型一推导出能体现出电极整体性质的模型的大小至少为15 μm,本文选定20 μm模型进行分析。然后通过改变模型中导电相的体积分数进行有效电导率和有效扩散系数的计算分析,最后得出了有效电导率与导电相的体积分数之间的函数关系和有效扩散系数与孔隙率之间的函数关系。
毕业论文关键词:SOFC;电极模型;有效电导率;有效扩散系数
Abstract The solid oxide fuel cell (SOFC) has been a huge boost compared to the previous after many years of development。 Various properties of SOFC electrodes plays a crucial role to overall performance, so the effective properties of the electrode become a very important issue, especially on the effective conductivity and effective diffusion coefficient。
The first chapter introduces the energy content of the current situation and the background of the fuel cell in the world currently, and then introduces the principle, composition, advantages and disadvantages of the fuel cell, and then focuses on the history of the development of solid oxide fuel cell electrodes and the composition of electrode。
The second chapter is the main content of the model。 the first introduction is EDEM software used by model, then the model is seen as SOFC electrodes Spheres piled up, and then use the software to build models of different sizes, depending on the differences of the particles herein built a total of three models。
The third chapter is the main content of the model process。 During processing model in this paper we have taken a dot instead of bulk particles thought。 Firstly, the model is equivalent to MATLAB software processing, and then re-import the model in COMSOL software to enable it to calculate the effective nature of the analysis。
The fourth chapter is the calculation and analysis of the model。 First, according to a model derived model to reflect the overall nature of the electrode size at least 15μm, 20μm model selected herein analyzed。 Then calculate the effective conductivity and effective diffusion coefficient analysis model by changing the volume fraction of the conduction, The conclusion that the function between the effective conductivity and the volume fraction of conductive phase, and also get the function between the effective diffusion coefficient and porosity。
Keywords: SOFC; Electrode model; Effective conductivity; Effective diffusion coefficient
目 录
第一章 绪论 1
1。1 研究的背景以及意义 1
1。2 燃料电池的简单介绍 2
1。2。1 燃料电池中的化学反应