9.3 Swirling and Rotating Flows

Many important engineering flows involve swirl or rotation and ANSYS FLUENT is well-equipped to model such flows. Swirling flows are common in combustion, with swirl introduced in burners and combustors in order to increase residence time and stabilize the flow pattern. Rotating flows are also encountered in turbomachinery, mixing tanks, and a variety of other applications.

For more information about the theoretical background of swirling and rotating flows, see this section in the separate Theory Guide.

When you begin the analysis of a rotating or swirling flow, it is essential that you classify your problem into one of the following five categories of flow:

• axisymmetric flows with swirl or rotation

• fully three-dimensional swirling or rotating flows

• flows requiring a rotating reference frame

• flows requiring multiple rotating reference frames or mixing planes

• flows requiring sliding meshes

Modeling and solution procedures for the first two categories are presented in this section. The remaining three, which all involve "moving zones'', are discussed in Chapter  10.