Modeling And Optimization For Transport And Adsorption In Porous Structures Of Carbon-based Materials For Hydrogen Storage

Carbon-based materials for hydrogen storage is a new hydrogen storage method in recent years. Due to its safety and reliability, light weight and shape choice convenience of hydrogen storage container, high efficiency of the hydrogen storage, it becomes a hot research spot for hydrogen storage. Carbon-based materials for hydrogen storage is used in low-temperature and high pressure for its high specific surface area. This thesis uses computational fluid dynamics software Fluent to explore absorption and transmission mechanism of porous structure in carbon-based hydrogen storage materials, model the process of transmission and absorption, achieve optimal design.At first, this thesis researches Dubinin-Astakhov model in the whole wide range of the temperature and pressure. Use the experimental data of the institut de recherche sur l'hydrogène, Universitédu QuébecàTrois-Rivières to fit the D-A model. Therefore, the absolute adsorption and excess adsorption can be calculated.Then, this thesis researches flow and heat transfer model in the porous structure of carbon-based hydrogen storage materials from mass, energy and momentum conservation point of view. Then, the mass source, energy source and momentum source which modeling charge process needs can be get. This thesis also models the flow in the porous structure of carbon-based hydrogen storage materials based momentum conservation and researches the influence of viscous resistance and inertial resistance when fluid flow through porous media.Based on the research of previous chapters, this thesis uses Fluent software to model charge process in hydrogen storage tank filled with activated carbon, solves the dynamic distribution of density, temperature, pressure, adsorption amount and adsorption source and compares the Fluent results to experimental results. The results show that the modeling results are similar to experimental results, the center region has high temperature and surrounding region has low temperature, In addition to the entrance, the trend of temperature at other location are increased first and then reduced, all of reason make the amount of hydrogen absorption in the surrounding region are more than center regional. The results also show that although the volume has a difference of three times, the amount of compression and absorption that storage hydrogen has difference of only about 1.5g, this shows that carbon-based materials for hydrogen storage has great advantages.Finally, this thesis researches the influence of model parameters such as mass flow rate, heat transfer condition, cooling way and hydrogen storage tank model to charge process. The results show that less mass flow rate can reduce the maximum temperature generating in the tank, the thermal conductivity of the adsorbent bed is the key to the temperature in the model; use a smaller or larger scale of radius to length storage tank in favor of heat transfer to outside.