Abstract
In order to realize the low temperature and rapid cold start-up of a proton exchange membrane fuel cell stack, a dynamic model containing 40 single proton exchange membrane fuel cells is established to estimate the melting time of the proton exchange membrane fuel cell stack as well as to analyze the melting process of the ice by using the obtained liquid–solid boundary. The methods of proton exchange membrane electric heating and electrothermal film heating are utilized to achieve cold start-up of the proton exchange membrane fuel cell (PEMFC). The fluid simulation software fluent is used to simulate and analyze the process of melting ice. The solidification and melting model and multi-phase flow model are introduced. The pressure-implicit with splitting of operators algorithm is also adopted. The results show that both the proton exchange membrane electric heating technology and the electrothermal film heating method can achieve rapid cold start-up. The interior ice of the proton exchange membrane fuel cell stack melts first, while the first and 40th pieces melt afterwards. The ice melting time of the proton exchange membrane fuel cell stack is 32.5 s and 36.5 s with the two methods, respectively. In the end, the effect of different electrothermal film structures on cold start-up performance is studied, and three types of pore diameter electrothermal films are established. It is found that the electrothermal film with small holes melts completely first, and the electrothermal film with large holes melts completely last.
Highlights
Proton exchange membrane fuel cells (PEMFCs) are a novel power generation technology which has a broad application prospect
We introduce the constant power density as the input condition and utilize two heating methods to achieve cold start-up: one is to heat by the proton exchange membrane (PEM), and another is by the electrothermal membrane (ETF)
It can be seen that the temperature of each layer gradually increases with time, the proton exchange membrane (PEM) temperature is the highest, and the temperature of the catalyst layer (CL), gas diffusion layer (GDL), ICE, and gas flow channel (GFC) layers is relatively lower, and the temperature of the bipolar plate (BP) layer is the lowest
Summary
Proton exchange membrane fuel cells (PEMFCs) are a novel power generation technology which has a broad application prospect. The main methods to solve the low temperature cold start of the fuel cell vehicles are to adjust the intake parameters, DC resistance heating, coolant heating, hot air purging hydrogen/oxygen catalytic reaction in the PEMFC, etc. Numerical calculations are carried out as follows: a two-phase non-steady-state model for cold start of a 40-layer two-dimensional PEMFC stack is established to track the solid/liquid interface and analyze the melting process in a PEMFC stack. Based on this model, the PEMFC stack heating and melting process is analyzed under the condition of residual water in the reactor before the start-up and the melting time of the PEMFC stack is predicted. All the above unit of variables are summarized in Appendix C
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call