留学生Essay作业：光学性质成像方法存在的缺点分析
从本文建立的测量收集和在场的液态水总量的质子交换膜燃料电池内操作自然是至关重要的理解和识别注水性质或膜的死虽然很难执行相同的(公园et al .,2008)。提出了在燃料电池运行前和运行后称重是测量液态水形成量的基本方法之一。还有一些其他的非原位测量可以用来诊断和分析PEMFC中水的分布。这些测量范围从经验技术到气相色谱法(PARK et al.， 2008)。已经有研究表明，液体水的形成和运动是可视化的，在流动通道内使用流动通道，可以通过光学和数字摄影。
留学生Essay作业：光学性质成像方法存在的缺点分析
然而，本文指出这些传统的光学性质成像方法存在一些缺点。缺点包括通道表面条件的变化和由于通道内饱和气流和高温而造成的窗口起雾。因此,开发先进的测量的成像技术,如量化的中子照相液态水分布和数量的PEM燃料电池的特性,因为敏感的中子在水中氢的原子(公园et al .,2008)。这可以通过对质子交换膜燃料电池(PEMFC)结构中涉及气体流动通道和气体扩散层(GDLs)的液态水积聚进行定量来实现。
留学生Essay作业：光学性质成像方法存在的缺点分析
It is established from the article that the measurement of the collection and total amount of the liquid water present within the PEMFC of operating nature is critical to understand and identify the water flooding nature or the dying of the membrane even though it is difficult to perform the same (PARK et al., 2008). The article suggested that one of the basic methods for the liquid water formation’s measurement in terms of amount is to weigh the fuel cell prior and after the operation of the cell. There are several other ex situ measurements that can be employed for the diagnosis and analysis of the distribution of water among the PEMFC. These measurements range from the empirical techniques to the gas chromatography (PARK et al., 2008). There have been studies in which the formation and movement of the liquid water were visualized within the flow channels using the flow channels that were accessible optically along with the digital photography.
留学生Essay作业：光学性质成像方法存在的缺点分析
However, the article indicated that there are several disadvantages of these conventional imaging method of optical nature. The disadvantages range from change in channel surface conditions and windows fogging because of the saturated stream of gas in the channels of flow and high temperatures. Hence, advanced measurements were developed in terms of the imaging techniques such as the neutron radiography for the quantification of the liquid water’s distribution and amount present in the fuel cells of PEM nature because of the sensitive of the neutron to the atoms of hydrogen within the water (PARK et al., 2008). This can be performed with the liquid water accumulation’s quantification across the structures of the PEMFC involving the channels of gas flow and gas diffusion layers (GDLs).
