Numerical Simulation Of Optimization On Performance In Direct Liquid Fuel Cells

As a portable high energy power source,the Direct Methanol Fuel Cell?DMFC?has a broad market prospect.But its marketization process has always been hampered by several problems,such as methanol penetration,slow oxidation kinetics of methanol oxidation,gas-liquid two-phase mass transfer on anode side.In order to mitigate the problems mentioned above,a series of scientific research has been carried out by the relevant personnel.The Direct Methanol Fuel Cell?DMFC?will produce carbon dioxide and water when working.The carbon dioxide from the anode product must be removed from the anode flow channel smoothly,so as to ensure the stable operation of the direct methanol fuel cell.The carbon dioxide produced in the anode catalyst layer is basically gas phase and is excluded through the anode channel.In the process of carbon dioxide bubble separation,carbon dioxide gas produces a strong gas-liquid two phase flow in the anode channel and methanol solution,which will cause the anode channel to produce a larger pressure drop and cause the performance degradation,making the research of direct methanol fuel cell more difficult.Based on the working principle of direct methanol fuel cell?DMFC?,a gas liquid solid mathematical model is established by combining the mass conservation equation,energy conservation equation,momentum conservation equation,and component conservation equation.The aim of this project is to explore the optimum working condition of direct methanol fuel cell.First of all,COMSOL Multiphysics is used to simulate the operation of DMFC,and the influence of operation parameters on DMFC performance is analyzed.Secondly,the magnetic field is introduced into DMFC to accelerate the performance of the battery by accelerating the stripping of CO₂ bubbles.Finally,the simulation analysis results are verified by experimental research.The results of the DMFC study are as follows:?1?The DMFC was numerically simulated by COMSOL Multiphysics,and the performance change was studied by changing the temperature and concentration of methanol feed.The results show that the performance of the battery is the best when the concentration of methanol is 2mol/L and the temperature is 75?.The performance of the battery will increase with the increase of the flow rate of methanol solution.At the same time,the reasons for the effect of various operating parameters on the performance of DMFC are also analyzed.?2?In order to improve the performance of the direct methanol fuel cell,the magnetic field was introduced into it.The Lorenz force was used to exfoliate the carbon dioxide bubbles from the surface of the anode catalyst layer.The physical barrier of the reactant and the anode catalyst surface was obviously relieved,and the performance of the battery was increased by 10%.?3?The performance test bench is established,and the results of numerical simulation are verified by experiments.The results show that the experimental results are basically consistent with the simulation results,and the error is less than5%,which meets the engineering requirements.The results provide a reference for optimizing the performance of the battery,realizing the stable and efficient operation of the direct methanol fuel cell.It provides a new idea to alleviate the two phase flow on the anode side,and is of great significance to the application of the application of the direct methanol fuel cell technology.