Graphics of the Flow Field Solution

There are many ways to examine the flow field results, some of which are described below. 

2 Streamlines. In 2D simulations, a quantity called the stream function, lJf, is defined in terms of the density and gradients of the x- and y-components of the velocity, U and V. In terms of cylindrical coordinates, which are most appropriate for axisymmetric stirred tank models, the definition takes the form 

5 Isosurfaces. Isosurfaces in 3D flow fields are analogous to contour lines in a 2D flow field. These 3D surfaces are constructed in such a way that a particular variable has a constant value everywhere on it. If the isosurface has a constant value of the Cartesian coordinate x, for example, it is planar. If it 

6 Particle Tracks. Whenever the discrete phase model is used (Section 5-2.2.2), particle tracks can be used to illustrate the trajectories of the particles, bubbles, or droplets. Trajectories can usually be displayed in a number of ways. For example, lines can be colored by the time of the trajectory or temperature of the particle itself. In addition to lines, ribbons and tubes can generally be used. The tracks can be computed and displayed using the mean fluid velocities, or in the case of turbulent flows, using random fluctuations in the mean fluid velocities as well. These stochastic tracks often give a more realistic picture of the extent to which the particles reach all comers of the solution domain than do tracks computed from the mean velocities alone. 

Time-Dependent Simulations. For time-dependent flow fields, images should be made at uniform time intervals for the purpose of creating a meaningful animation. Examples of time-dependent animations include 

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