Visualizing Turbulent Flow Features Using Surfaces

How can I visualize turbulence and flow features using surfaces?
The Q criterion, introduced by Hunt et al. in 1988, is commonly used to identify regions of recirculation in flow fields.

As of FieldView version 17, Q-criterion is a built-in function available on the Function Calculator, increasing peformance as compared to using this function via feature_detection_formulas.frm available with previous versions of FieldView.