机械装置湍流瞬态.pdf

Solved with COMSOL Multiphysics 4.3a Turbulent Mixing of a Trace Species Introduction This tutorial demonstrates how mixing can be simulated in a stirred vessel by seeding a trace species from a point. The flow is modeled using the Rotating Machinery, Fluid Flow physics which solves Navier-Stokes equations on geometries with rotating parts, for example impellers. The transport of the trace species is modeled using the Transport of Diluted Species interface. Model Definition M O D E L G E O M E T R Y Figure 1 shows the model geometry which is s a schematic cross-section of a tank with a four-blade impeller. The tank has four baffles attached to the wall to enhance mixing. The seeding of the trace species is done at the marked point. The circle between the impeller and the tank wall is the assembly boundary where the mesh is allowed to slide when the impeller rotates. © 2 0 1 2 C O M S O L 1 | TU R B U L E N T M I X I N G O F A TR A C E S P E C I E S Solved with COMSOL Multiphysics 4.3a Seeding point Rotational direction Assembly boundary Figure 1: Model geometry. D O M