Transport processes and numerical simulation of DNAPL contaminants in saturated sandy soils
In this paper,based on the parameters obtained from the physical sandbox experiment,the numerical simulation Petrasim program was utilized to simulate the migration process of DNAPL in saturated porous media,which has certain research significance in exploring the migration behavior of DNAPL under the combined action of gravity and capillary force and the contaminants distribution characteristics in the migration paths.The numerical results and experimental data showed that:(1)in the early stage of infiltration,DNAPL was mainly affected by gravity and showed"droplet"vertical diffusion.After vertical diffusion to the bottom impervious layer,DNAPL began to redistribute and spread laterally driven by capillary force,and finally forms a long-term"pool"contaminant source area at the bottom of sandbox;(2)By comparing the simulation results with the experimental data,the relative error range of the vertical diffusion was-2.96％～5.95％.The relative error range of horizontal diffusion was 0.04％～23.41％,and the relative error range of plane contamination area was 0.03％～19.39％.The fitting determination coeffiicients R2 which characterize the differences between the simulated values and the experimental data of horizontal diffusion,vertical diffusion and contaminant area were 0.8827,0.9919 and 0.9832,respectively.The simulation results were close to the experimental data,which is satisfactory.The reliability and accuracy of numerical simulation Petrasim program in predicting DNAPL migration behavior and contaminant distribution in saturated porous media were investigated in this study.Indicating that the assessment of DNAPL leakage range and the prediction of DNAPL migration behavior have broad application prospects in the field environment.
dense non-aqueous phase liquiddistribution of contaminantsnumerical simulationsaturated sandy soils
万方数据
维普
