Research Of Coal Additives And Simulation Of Flow In Porous Media By The LES-LBM Coupling Method

Our China has become the biggest energy consumer in the world, and the consumption of coal make up a significant portion of the terminal energy struction. The mainly way to use coal is combustion, though the most serious pollutant is brought which is dangerous to human health and environment development. So the government has made strict standards of pollutant emissions for sustainable development, what has become a huge challenges to the control technology of pollutant discharge. In this paper, we simulated the migration and transformation of volatile-N with chemical kinetics and additive affect during the combustion of coal, at the same time a novel coupling lattice boltzmann method is created to simulate non-linear phenomena of the flow in porous.First, a plug flow reactor model with detail chemical kinetics is created to study the migration and transformation properties of volatile-N which include HCN and NH3. The current results show that temperature is the most sensitive parameters impacting the formation of N2O where exists a optimum temperature, the formation of NO increases with temperature. CO can introduced a mount of free radicals enhanceing the intermediate reaction which will increase the formation of NO and N2O, and the final products are impacted by the propartion of HCN and NH3, the formation of N2O is suppressed with H2O introducted.Second, the influence of coal-burning additive is studyed in the one-dimensional furnace. Grouping experiments for different coal samples and mixing ratio and coal additives are carried out. The results show that the coal additive can promote combustion efficiency, and reduces the NOx emissions at the same time. In the last, several industrial applications approaches are discussed.Finally, The non-linear phenomena of single-phase flow in porous media with various Reynolds numbers are studied by using the LES-LBM coupling method. Results show that the LES-LBM coupling method has more advantages than the traditional LBGK method in numerical stability. The flow in porous media covers three regimes when Reynolds numbers are increasing, which are the Darcy, the no-Darcy and the transition regimes. It is also found that flow in porous media has obvious features of multiscale, and the microscopic inertial effect is the main factor that leads to deviation from the linear Darcy regimes to the no-Darcy regimes when streamlines observation is interested. The current results are in good agreement compared with existing experimental and numerical data. Darcy-Forchhimer drag increases with Reynolds numbers but decreases with porosity, and ratios of Forchhimer darg increases quickly with porosity.