The Study On Direct Numerical Simulation Of Glucose Fuel Cell

The rapid development of embedded systems, micro-and nano-technology is becoming a trend In the ideal situation, these components should better be able to supply power. The body has provided the massive latent chemical energy (glucose), if actuates with the biology fuel cell the miniature blood sugar density instrumentation, may implant it to some blood vessel pipe wall on, when its extraction blood's blood sugar analysis, may through the bringing biology fuel cell, the extraction partial blood sugars, the use glucose electricity generation, on the one hand maintains own energy, on the other hand may produce the electromagnetism signal, to outside transmission about blood sugar density information, thus achieves the long time monitor blood sugar the function. The enzyme biology fuel cell is the fuel cell research key point, because its volume is small, the biological compatibility is good, may use to implanting human body's organ power supply. The biology fuel cell appeared most early in 1964, was implants in vivo the pacemaker to provide the power source, but because the battery had the electric quantity to be small but has not realized the marketability.Because the enzyme is now an internal fuel cell electrochemical reaction and mass transfer process and the process of the impact on battery performance and lack of knowledge and experimental fuel cell costly, long time, so based on fuel cell thermodynamics, reaction kinetics of the glucose fuel cell principle The current process of numerical simulation have an important theoretical and engineering application value.Modeling of fuel cell systems need to theoretical analysis, combined with the battery material and structural characteristics, the use of energy, quality, conservation of momentum equation, as well as electrochemical, thermodynamic and kinetic theory to establish cell models, in order to take full advantage of these experimental results model to verify the accuracy of model parameter derivation, both the theoretical model or empirical model of the right to establish, in the research and to improve battery performance, it can help people a better understanding of cell processes and phenomena occur, in order to optimize the electrode the structure of the battery operating conditions and provide a theoretical basis; in the design of fuel cell system is conducive to a reasonable choice of control variables and control strategy to ensure that the fuel cell to high-performance, high reliability and long life operation.Mathematical model of the fuel cell is divided into the following categories:First, analysis of the model. Analytical model does not involve the internal battery material transfer and electrochemical reaction mechanism analysis model contains many assumptions, the general model are based on flat-panel electrodes to create the corresponding governing equations, so the role model is very limited, only applies to the need for rapid qualitative simple calculation applications.Second, semi-empirical model. A combination of semi-empirical model of the theory of differential / algebraic equations and the empirical equation. Semi-empirical model used in the general description of physical phenomena, it will be difficult, or the study of the phenomenon is not entirely theoretical description of the occasion. Empirical model only under certain operating conditions effective, can not accurately predict the properties outside the scope of the battery; Experience in forecasting equation may have been the completion of the battery design is effective, but can not be used to predict the new design based on the performance of the battery; At the same time, the experience of the model can not be used to understand the internal battery of physical and chemical processes, but only in between input and output related.Third, the mechanism of the model. Mechanism model of the battery based on the internal control process of the physical and electrochemical generation of a number of differential equations, numerical method for solving the general adoption. Mechanism model can be further divided into multi-regional model and single-zone model. Multi-regional model: multi-regional model of the battery within the different regions of each are listed in the control equations were solved, the calculation of the region include: cathode and anode diffusion layer, flow field, proton exchange membrane and catalyst layer and so on. At the same time they were solving equations. Single-region model: the different models and multi-regional, regional model of a single fuel cell model attempts to calculate the entire region as a whole, all regions of the calculation equations of conservation of mass equations are used in each sub-region, the different equations and convergence is the source of the different items, all equations can be written in a unified convection - diffusion equation, and the reunification of convection - diffusion equation can be easily applied in computational fluid dynamics (CFD) software to solve.In this paper, the major multi-regional model of the glucose fuel cell for one-dimensional modeling analysis of the electrochemical process of the battery, charge transfer and mass transfer processes are described, the establishment of the battery cathode and anode diffusion layer, dielectric layer and catalyst layer control equation. In the mathematical model, based on the battery with a matlab simulation analysis. Analysis of the anode and cathode potential had been potential impact on battery performance; glucose concentration on the impact of battery performance, battery performance degrees electrode thickness, as well as the impact of temperature on battery performance.