Nanoparticles Enhance The Molecular Dynamics Simulation And Model Study Of Gas-liquid Mass Transfer

The research on nanoparticle enhanced gas liquid mass transfer can be derived from various fields in real life,and the research on nanoparticle enhanced mass transfer also has broad prospects.The existing research is more based on macroscopic experiments,summarizing experimental phenomena,and conducting mechanism research at the macroscopic level.However,further research is needed on the microscopic characteristics of nanoparticles during enhanced mass transfer.Molecular dynamics simulation can be used to study the process of enhancing mass transfer at the atomic scale,filling in some shortcomings of conventional experiments.Firstly,this article introduces the research status of nanofluid enhanced mass transfer and the research progress of mathematical models,and details the basic principles of molecular dynamics simulation,mainly focusing on the algorithm,time step,potential energy function,boundary conditions,and ensemble in the MD simulation process.Subsequently,the mass transfer process of nanoparticle enhanced deionized water absorbing oxygen was simulated using LAMMPS software,and the establishment of the simulation system and command invocation were described in detail.Research has found that in the simulation system,adding nanoparticles can effectively enhance mass transfer;When the diameter of nanoparticles remains unchanged,the diffusion coefficient of nanoparticles and the number of oxygen molecules absorbed by deionized water will first increase and then decrease as the number of nanoparticles increases;When the number of nanoparticles remains constant,the diffusion coefficient of nanoparticles and the number of oxygen molecules absorbed by deionized water decrease as the particle size increases.In addition,this article also explores the enhancement mechanism of mass transfer from a mathematical model.Based on the dual mode theory,a three-dimensional unsteady model for studying the enhancement of oxygen absorption by sodium sulfite solution by nanoparticles was established from the perspectives of transport mechanism,Brownian motion,and the effects of chemical reactions.Comparing the calculated enhancement factor of the three-dimensional unsteady model with the experimental enhancement factor,the average error is less than 3.72%.The accuracy of the model was verified,providing a reference for research in the field of modeling.