论文总字数：16903字

摘 要

质子交换膜燃料电池是21世纪的一个非常重要的产业之一。燃料电池的各个部件都会对其性能有着非常重要的影响，例如双极板的厚度，流道的形状和尺寸等等。本文以CFD数值模拟技术为理论基础，从不同的流道截面结构方面研究了其对燃料电池的性能影响。得出的结论如下：

(1) 模拟实验的结果表示，因为矩形截面和梯形截面的阳极和阴极的进口电压都设置的很小，两种不同的截面内流道的电流密度相差并不是很大，并且整个截面的整体电流密度分布都很稳定，但是，随着设置的流体不断地进入流道，局部的电流密度变化明显加大，流道内的整体的电流密度也发生了变化：然而矩形截面和梯形截面的阴极电流密度分布变化较小，两个截面的电流密度在流体流入后都逐渐变小了。

(2) 模拟实验的结果表示，在矩形截面和梯形截面下，氧气浓度大致上的分布规律一样，阳极和阴极双极板的氧气浓度都是从进口逐渐降低到出口。

(3) 模拟实验的结果表示，在温度方面，阳极流道和阴极流道差别较大，阳极流道方面，电池温度基本上都是在300K左右，变化不是很大：而在阴极流道方面，温度基本不变，徘徊在343K左右，然而温度变化在阴极的出口处突然减小，从343K直接较少到了300K。从整个梯形和矩形截面来看，矩形截面的变化规律与梯形相同，没有多大的不同。

(4) 模拟实验的结果表示，燃料电池的矩形截面和梯形截面在阳极流道处的压力变化在200000Pa的压力和0.75V的电压作用情况下，进行反应的结果表示，两种截面的流道压力变化一样，都是进气口的压力最大，接着是压力在慢慢的变小，在电池不断地发生反应下。随着流道中的流体不断的流动和电池不断进行的反应，压力也随着不断变化，流体一直是流向压力降低的地方：阳极和阴极的整体压力变化趋势相同。

关键词：质子交换膜燃料电池 双极板 矩形截面 梯形截面 性能研究

ABSTRACT

Proton exchange membrane fuel cell is one of the most important industries in the 21st century. Every part of fuel cell will have a very important impact on its performance, such as the thickness and depth of bipolar plate, the shape and size of flow channel and so on. This paper use the CFD numerical simulation technology to discuss the effecrt of different channel cross-section structure on the PEMFC. The conclusions are as follows:

(1) The results of the simulation experiment show that the current density of the channel in the two different sections is not very different, and the overall current density distribution of the whole section is very stable, because the inlet voltage of the anode and the cathode of the rectangular section and the trapezoid section are set very small, but as the set fluid continuously enters the channel, the local current density changes significantly, the channel However, the current density of the rectangular section and the trapezoid section changed little, and the current density of the two sections decreased gradually after the flow.

(2) Simulated results show that in the rectangular section and trapezoidal cross section, the oxygen concentration of the anode and cathode bipolar plates gradually decreases from the import, as in the almost all the distribution rule of oxygen concentration.

(3) Simulated results show that the temperature difference between the positive and negative channels is large. In terms of anode channel, the battery temperature is basically around 300K, with little change. In the negative passage, the temperature does not change fundamentally and is wandering around 343 K.However, the temperature change suddenly discreases at the outlet of cathode, from 343K to 300K. From the whole trapezoid section and rectangular section, the changes of the two sections are the same, there is not much difference.

(4) As a result of simulation experiments, it was shown that the pressure change in the rectangular section of the fuel cell and the positive channel of trapezoidal cross section was under the pressure of 2000 PA and the voltage action of 0.75V. The results of reaction show that the pressure changes of the two sections are the same, the pressure of the air inlet is the largest, and then the pressure slowly decreases, under the constant reaction of the battery. With the continuous flow of the fluid in the flow channel and the continuous reaction of the battery, the pressure also changes constantly, and the fluid has always been the place where the flow pressure decreases: the overall pressure change trend of the anode and cathode is the same.

KEYWORDS:Proton exchange membrane fuel cell；Bipolar plate；Rectangular cross section；ladder-shaped cross section；Performance study

目 录

摘 要 I

ABSTRACT II

第一章 绪论 1

1.1 PEM燃料电池的探究背景 1

1.2 PEM燃料电池基本介绍 1

1.3 PEM燃料电池流场发展动向 3

1.4 研究的主要内容 5

第二章 PEM燃料电池几何模型和数值模型的建立 7

2.1 几何模型的建立 7

2.2 网格化控制 8

2.3 数值模型的建立 10

2.3.1 边界条件的设置 10

2.3.2 收敛性设置 20

第三章 模拟结果及分析 22

3.1 电流密度结果及分析 22

3.2 氧气浓度结果及分析 23

3.3 温度结果及分析 24

3.4 压力结果及分析 26

3.5 本章小结 28

第四章 结论和展望以及经济性评价 30

4.1 结论 30

4.2 展望 30

4.3 经济性评价 31

参考文献 32

致 谢 35

第一章 绪论

1.1 PEM燃料电池的探究背景

自从，煤炭，石油这些化石能源被发掘出来，被人们大量的利用，在工业革命开始的时候，几乎各个领域都有他们的身影。但是这些化石能源的缺点也是非常多的，比如说污染很大，利用的效率低，而且用完之后就没有了，很大的限制了社会的进步和发展。于是，人类就开始在自然界中摸索，企图寻找没有污染的，能够再生的新能源，比如风能，水能，地热能，潮汐能等等。作为其中之一的质子交换膜燃料电池（PEMFC），因其不腐蚀，使用周期长，污染小，快速启动等特点，被人们广泛的使用[1]。

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