Simulation Of Charging Process Research Articles

Conventional and nano-enhanced Phase Change Material melting simulation by using Lattice Boltzmann method: A comprehensive review

Phase Change Materials (PCMs) are latent heat energy storage mediums that have received considerable attentions regarding their high heat capacity and applicability for other purposes such as thermal management. Numerical simulation has been applied for these materials to investigate their heat transfer characteristics such as the rate of phase change and energy storage capacity. Lattice Boltzmann method is a promising approach for modeling and simulation of PCMs in both charging and discharging processes. In this article, studies on the melting (charging) of PCMs, with and without existence of nanomaterials, are reviewed and their results are represented and summarized. Corresponding to the findings of the reviewed studies it can be concluded that this approach is able to properly simulate the melting process of various PCMs. Simulation of charging process by means of this method showed that the melting rate is improvable by employing different ideas namely adding nanomaterials, using fins and heat pipes. Applying these ideas have significant impact on melting rate under specific conditions, i.e. more than 52% improvement in the melting rate for adding Cu nanoparticles with 4% concentration. Finally, some recommendations are suggested for the forthcoming studies in this field.

Mathematical simulation of charging process for porous cadmium electrode of alkali batteries

A mathematical description of the process of cadmium electrode charging is presented. It allows evaluating the dependence of cathodic polarization on the concentration of alkali electrolyte, charging current density, electrode thickness and porosity. It was taken into account in the calculation that cathodic reduction of the cadmium electrode occurred via the liquid-phase and solid-phase mechanisms, diffusion, migration, and convective transport of components of electrolyte. Calculations according to the suggested model showed its applicability to sintered cadmium electrodes.

Speed-up of computing time for numerical analysis of particle charging process by using discrete element method

The objective of this paper is to improve the computing time for numerical analysis of particle charging process by using discrete element method. The rule for ignoring the calculations of contact forces and updating trajectories of unmoved particles were discussed. When the relative displacement of a particle within certain calculation steps became less than 0.1% of particle radius, this particle was determined to be unmoved and the calculations of this particle were ignored. The computing time was improved significantly when this new method was used, and its calculation speed was more than two times faster than that of original. It was found that this speed-up method is more useful for the cases that the particle becomes unmoved in short time or the height of charged bed is large. The simulation of charging process in an industrial-scale surge hopper was studied by using new method, the calculation speed became 2.88 times faster than that of original, and the quite similar particle size segregation between original and new methods was given. This new method for speed-up of the charging process in DEM is very useful, and the charging processes of the industrial scale storages can be simulated by using this method.