Water-thermal Management System Simulation Of Proton Exchange Membrane Fuel Cell

Proton exchange membrane fuel cell has the following advantages: its generation process does not involve hydrogen-oxygen combustion, and thus not subject to Carnot cycle limit, the energy conversion rate is high; electricity without pollution, power generation unit modular, high reliability, assembly and maintenance of very convenient to work, they do not have noise. Therefore, the proton exchange membrane fuel cell is a clean, efficient green power.This article uses the computer simulation method to analyze the proton exchange membrane fuel cell thermal management of water, using computational fluid dynamics software Fluent in PEM module calculated. Flow channel were set up five proton exchange membrane fuel cells and the cooling channel 5 with a flow channel model for proton exchange membrane fuel cells for analysis.Flow channel of the five proton exchange membrane fuel cell was simulated, obtained the lower operating voltage, current density, the greater the battery internal temperature the higher the temperature the greater the proton exchange membrane, the easier dehydration, the worse the reliability of the battery's work , the higher the voltage, current density, the smaller the battery internal temperature the lower the temperature the smaller the proton exchange membrane more difficult to dry, the stronger the reliability of the battery's work.On this basis, to explore the extent and the porosity of the humidification on fuel cell performance and temperature distribution in the results that they do not wet the battery when the first half of the molar concentration of water is too low membrane, membrane dehydration serious, membrane rupture resulted in easy to H2, O2 mix, or even an explosion. Cathode humidification water, the mass fraction of 0.3, anode humidification water quality score of 0.3, the entire cell membrane of the molar concentration of water in a more reasonable level, the membrane water content is moderate, at this time of the wetting film in good condition, batteries water balance at its best. More uniform temperature distribution membrane, membrane water content increases, its resistance decreases, membrane conductance increased, the chemical reaction of aggravated battery performance enhancements. To change the porosity of the membrane temperature distribution is very small, very small membrane temperature, indicating the pore size is not affecting the rate of temperature change inside the main reason for the battery.Establishment of the cooling channel 5 with a flow channel of proton exchange membrane fuel cell model, the cooling water flow rate of 0.1m / s when the flow channel along the direction of the maximum membrane core temperature, cooling water flow rate of 2m / s when the flow channel along the direction of film core temperature minimum. Cooling water flow rate along the flow channel direction of the temperature distribution in film center is relatively small. Cooling water temperature is 10℃, the direction of flow channel along the membrane core temperature minimum, cooling water temperature is 60℃, the direction of flow channel along the membrane core temperature up. In the cooling water temperature is 20℃, not only to achieve the purpose of cooling, but also does not cause the temperature is too low and the lower part of the initial extent of electrochemical reaction. Cooling water flow channel along the downstream direction when the membrane core temperature lower than when the cooling water upstream, downstream and upstream of the cooling water flow direction along the membrane core temperature of not very different.