  A new approach is shown, which estimates active grid wake features and
enables to generate specific dynamically changing flow fields in a wind tunnel
by means of an active grid. For example, measurements from free field can be
reproduced in a wind tunnel. Here, the approach is explained and applied.
Moreover, the approach is validated with wind tunnel measurements, in terms of
time series and stochastic features. Thus, possibilities and limitations become
obvious. We conclude that this new active grid wake estimating approach deepens
the knowledge about specific flow modulations and shows new working ranges of
active grids.
