質(zhì)子交換膜燃料電池裝配力學及其對性能影響的研究
發(fā)布時間：2019-04-18 22:19
【摘要】：質(zhì)子交換膜燃料電池(Proton Exchange Membrane Fuel Cell,PEMFC)是一種通過電化學反應(yīng)將燃料的化學能直接轉(zhuǎn)化成電能的能源轉(zhuǎn)換裝置,由于其燃料來源廣泛、清潔無污染、工作電流大和常溫下啟動快等優(yōu)點,被認為是最有發(fā)展前景的清潔能源轉(zhuǎn)換裝置之一。PEMFC各組件之間需要通過從外部施加壓力進行組裝,由于氣體擴散層(Gas Diffusion Layer,GDL)為多孔結(jié)構(gòu)且彈性模量相對較小,施加壓力時,若裝配壓力過大,會造成GDL的過度變形甚至是不可逆的破壞,導(dǎo)致氣體傳輸通道減小,傳質(zhì)阻力增加,同時也可能會損壞燃料電池部件,縮短使用壽命;相反,若裝配壓力過小,會因為雙極板與GDL之間接觸不良,導(dǎo)致接觸電阻增大,使燃料電池的工作效率降低,且不能保證氣體的密封性,燃料氣體存在泄漏的危險。本文采用數(shù)值模擬的方法,對不同裝配壓力下GDL的變形進行模擬,并對由裝配壓力引起的GDL孔隙率、滲透率等傳輸參數(shù)的變化及其對PEMFC性能的影響進行深入研究,以期得到最佳裝配壓力,使得燃料電池性能最優(yōu)。論文主要工作和成果如下:建立單通道PEMFC幾何模型,采用數(shù)值模擬的方法進行仿真計算,并參考經(jīng)驗公式分別計算單通道PEMFC在不同裝配壓力下孔隙率、滲透率等傳輸參數(shù)和接觸電阻的變化。當裝配壓力為0-3.0 MPa時,孔隙率從初始值0.78下降到0.38左右;滲透率也發(fā)生了一個數(shù)量級之多的變化;雖然接觸電阻隨著裝配壓力的增加不斷減小,但電阻減小的幅度在逐漸降低;采用有限元分析法(Finite Element Analysis,FEA)分析不同裝配壓力對GDL變形的影響。研究結(jié)果顯示,在不同裝配壓力的作用下,位于雙極板兩側(cè)脊部下方的GDL會發(fā)生不同程度的變形,兩側(cè)變形情況相似且明顯,而且變形程度隨著裝配壓力的增加而變大,但位于流道下方的GDL則幾乎沒有變化,且GDL在X軸方向上的孔隙率隨裝配壓力的變化趨勢與GDL的形變趨勢相近;通過模擬仿真,分析比較不同裝配壓力下單通道PEMFC陰、陽極流道內(nèi)組分濃度的分布狀況以及各裝配壓力下的極化曲線。由于流道內(nèi)的反應(yīng)氣體在催化層(Catalyst Layer,CL)中會發(fā)生化學反應(yīng),因此在不同裝配壓力下氣體濃度均沿著流動方向減小。對于極化曲線而言,當裝配壓力為0.5-1.0 MPa時,相同工作電壓下,單通道PEMFC的電流密度大于其他壓力下的情況,且該裝配壓力下單通道PEMFC的功率最高。因此,當裝配壓力為0.5-1.0 MPa時,單通道PEMFC的性能最優(yōu)。
[Abstract]:Proton exchange membrane fuel cell (Proton Exchange Membrane Fuel Cell,PEMFC) is an energy conversion device that converts the chemical energy of fuel directly into electric energy by electrochemical reaction. Because of its wide source of fuel, it is clean and non-polluting. The advantages of large working current and fast start-up at room temperature are considered to be the most promising clean energy conversion devices. The components of PEMFC need to be assembled by applying pressure from the outside, because of the gas diffusion layer (Gas Diffusion Layer,. GDL) is a porous structure with relatively small elastic modulus. If the assembly pressure is too large, it will cause the excessive deformation or irreversible destruction of GDL, resulting in the reduction of the gas transport channel and the increase of mass transfer resistance. At the same time may also damage fuel cell components, shorten the service life; On the contrary, if the assembly pressure is too low, the contact resistance will increase due to the poor contact between the bipolar plate and the GDL, and the working efficiency of the fuel cell will be decreased, and the sealing property of the gas will not be guaranteed, and the leakage of the fuel gas will occur. In this paper, the deformation of GDL under different assembly pressures is simulated by numerical simulation method, and the change of transmission parameters such as porosity and permeability of GDL caused by assembly pressure and its influence on the performance of PEMFC are deeply studied. In order to obtain the optimal assembly pressure, the fuel cell performance is the best. The main work and achievements of this paper are as follows: the geometric model of single-channel PEMFC is established, and the porosity of single-channel PEMFC under different assembly pressures is calculated by means of numerical simulation, and the porosity of single-channel PEMFC under different assembly pressures is calculated according to the empirical formula. Changes in transmission parameters such as permeability and contact resistance. When the assembly pressure is 0 / 3.0 MPa, the porosity decreases from the initial value of 0.78 to about 0.38, and the permeability changes as much as an order of magnitude. Although the contact resistance decreases with the increase of assembly pressure, the extent of resistance decrease gradually. Finite element analysis (Finite Element Analysis,FEA) is used to analyze the effect of different assembly pressure on the deformation of GDL. The results show that under different assembly pressure, the deformation of GDL under the ridge of bipolar plate is similar and obvious, and the degree of deformation increases with the increase of assembly pressure, and the deformation of the two sides is similar and obvious, and the deformation degree increases with the increase of assembly pressure, and the deformation of the two sides is similar and obvious with the increase of assembly pressure. However, the GDL under the channel has almost no change, and the porosity of GDL in the direction of X-axis is similar to that of GDL in the direction of assembly pressure. Through simulation, the distribution of component concentration in PEMFC negative and anode channels and polarization curves under different assembly pressures were analyzed and compared. Because the reaction gas in the channel will react in the catalytic layer (Catalyst Layer,CL), the gas concentration decreases along the flow direction at different assembly pressures. As far as the polarization curve is concerned, when the assembly pressure is 0.5 MPa, the current density of the single channel PEMFC is higher than that of the other pressure at the same operating voltage, and the assembly pressure sends out the highest power of the order channel PEMFC. Therefore, when the assembly pressure is 0.5 / 1.0 MPa, the performance of single channel PEMFC is the best.
【學位授予單位】：浙江科技學院
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TM911.4
本文編號：2460338
[Abstract]:Proton exchange membrane fuel cell (Proton Exchange Membrane Fuel Cell,PEMFC) is an energy conversion device that converts the chemical energy of fuel directly into electric energy by electrochemical reaction. Because of its wide source of fuel, it is clean and non-polluting. The advantages of large working current and fast start-up at room temperature are considered to be the most promising clean energy conversion devices. The components of PEMFC need to be assembled by applying pressure from the outside, because of the gas diffusion layer (Gas Diffusion Layer,. GDL) is a porous structure with relatively small elastic modulus. If the assembly pressure is too large, it will cause the excessive deformation or irreversible destruction of GDL, resulting in the reduction of the gas transport channel and the increase of mass transfer resistance. At the same time may also damage fuel cell components, shorten the service life; On the contrary, if the assembly pressure is too low, the contact resistance will increase due to the poor contact between the bipolar plate and the GDL, and the working efficiency of the fuel cell will be decreased, and the sealing property of the gas will not be guaranteed, and the leakage of the fuel gas will occur. In this paper, the deformation of GDL under different assembly pressures is simulated by numerical simulation method, and the change of transmission parameters such as porosity and permeability of GDL caused by assembly pressure and its influence on the performance of PEMFC are deeply studied. In order to obtain the optimal assembly pressure, the fuel cell performance is the best. The main work and achievements of this paper are as follows: the geometric model of single-channel PEMFC is established, and the porosity of single-channel PEMFC under different assembly pressures is calculated by means of numerical simulation, and the porosity of single-channel PEMFC under different assembly pressures is calculated according to the empirical formula. Changes in transmission parameters such as permeability and contact resistance. When the assembly pressure is 0 / 3.0 MPa, the porosity decreases from the initial value of 0.78 to about 0.38, and the permeability changes as much as an order of magnitude. Although the contact resistance decreases with the increase of assembly pressure, the extent of resistance decrease gradually. Finite element analysis (Finite Element Analysis,FEA) is used to analyze the effect of different assembly pressure on the deformation of GDL. The results show that under different assembly pressure, the deformation of GDL under the ridge of bipolar plate is similar and obvious, and the degree of deformation increases with the increase of assembly pressure, and the deformation of the two sides is similar and obvious, and the deformation degree increases with the increase of assembly pressure, and the deformation of the two sides is similar and obvious with the increase of assembly pressure. However, the GDL under the channel has almost no change, and the porosity of GDL in the direction of X-axis is similar to that of GDL in the direction of assembly pressure. Through simulation, the distribution of component concentration in PEMFC negative and anode channels and polarization curves under different assembly pressures were analyzed and compared. Because the reaction gas in the channel will react in the catalytic layer (Catalyst Layer,CL), the gas concentration decreases along the flow direction at different assembly pressures. As far as the polarization curve is concerned, when the assembly pressure is 0.5 MPa, the current density of the single channel PEMFC is higher than that of the other pressure at the same operating voltage, and the assembly pressure sends out the highest power of the order channel PEMFC. Therefore, when the assembly pressure is 0.5 / 1.0 MPa, the performance of single channel PEMFC is the best.
【學位授予單位】：浙江科技學院
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TM911.4
【參考文獻】
相關(guān)期刊論文 前10條
1 趙東江;馬松艷;;燃料電池汽車及其發(fā)展前景[J];綏化學院學報;2017年05期
2 吉辰;胡桂林;;裝配壓力對PEMFC氣體擴散層影響的研究[J];浙江科技學院學報;2017年01期
3 周怡博;王建建;;裝配壓力對燃料電池擴散層影響的研究[J];系統(tǒng)仿真學報;2016年04期
4 沈俊;周兵;邱子朝;涂正凱;劉志春;劉偉;;質(zhì)子交換膜燃料電池強化傳質(zhì)[J];化工學報;2014年S1期
5 項忠曉;泮國榮;徐國峰;趙依;胡桂林;李國能;;基于ANSYS的PEM單電池組裝應(yīng)力分析[J];浙江科技學院學報;2013年01期
6 李文安;楊立軍;杜小澤;楊勇平;;陽極加濕對質(zhì)子交換膜燃料電池性能的影響[J];中國電機工程學報;2010年17期
7 吳俊榮;林維明;;新能源開發(fā)與可持續(xù)發(fā)展[J];廣州化工;2008年05期
8 毛宗強;黃建兵;王誠;劉志祥;;低溫固體氧化物燃料電池研究進展[J];電源技術(shù);2008年02期
9 方坤;;計算流體力學的幾種常用軟件[J];煤炭技術(shù);2006年12期
10 衣寶廉,俞紅梅;質(zhì)子交換膜燃料電池關(guān)鍵材料的現(xiàn)狀與展望[J];電源技術(shù);2003年S1期
相關(guān)博士學位論文 前3條
1 吳芝亮;質(zhì)子交換膜燃料電池接觸電阻數(shù)學建模與參數(shù)分析[D];天津大學;2008年
2 朱科;質(zhì)子交換膜燃料電池Pt/C電催化劑和膜電極的研究[D];天津大學;2005年
3 胡桂林;質(zhì)子交換膜燃料電池內(nèi)傳遞現(xiàn)象的數(shù)值模擬[D];浙江大學;2003年
相關(guān)碩士學位論文 前2條
1 李昌平;基于分支結(jié)構(gòu)的PEMFC雙極板流場結(jié)構(gòu)數(shù)值模擬與優(yōu)化[D];武漢理工大學;2011年
2 嚴蓉蓉;質(zhì)子交換膜燃料電池熱力耦合效應(yīng)影響分析[D];上海交通大學;2010年
，本文編號：2460338
本文鏈接：http://sikaile.net/kejilunwen/huagong/2460338.html
教材專著
