Research On A New Method To Calculate Flow Viscosity In Nanoflow Problems

With the rapid development of nano science and technology, nanometer scale fluidflow characteristic research has great practical significance. Viscosity fluid characteristicsas the important physical parameters, became the key issue of the study. This paper mostlyresearches the calculation method of velocity by using molecular dynamics simulation.Combined the relationship between flow and flow velocity in fluid mechanics andmolecular dynamics method, a new method to calculate flow velocity in nanoflow ispresented. First of all, to the traditional methods and new methods are introduced andcomparison of the system, is established for simulation calculation theory basis andpremise condition.Furthere more, a comprehensive investigation on the properties of confined fluid innano slit was carried out, three-dimensional liquid argon Poiseuille flows in a narrowconfined nanochannels are simulated. By changing wall-fluid interaction and externalforce, the flow velocities are calculated with this new method and the conventionalmethod, and the resulting parameters were analyzed. The results of the study show that,the new method for viscosity and traditional molecular dynamics method for viscosity areconsistent with each other. The attration force takes more effect on density distribution,compared with repulsive part. The highest calculated flow velocity of this new method ishigher than that of the traditional method, while the lowest calculated flow velocity islower than that of the tarditional method. Finally, cavity flow are established andsimulated, the flow velocities are calculated with two kinds of solution method of flowvelocity, then drawing out the velocity curves. By changing the mesh gird density andexternal force, different kinds of model are established. Through a great amount ofsimulations, calculational simulation results have been discussed and analyzed. It wasshown that, both of the methods are proved effective on different kinds of model, but thespeed of varies in boundary. In contrast, the new method can get the optimal value morequickly and the calculations will be more accurate in boundary problem of velocitycomputation.