  Installation noise is a dominant source associated with aircraft jet engines.
Recent studies show that linear wavepacket models can be employed for
prediction of installation noise, which suggests that linear control strategies
can also be adopted for mitigation of it. We present here a simple model to
test different control approaches and highlight the potential restrictions on a
successful noise control in an actual jet. The model contains all the essential
elements for a realistic representation of the actual control problem: a
stochastic wavepacket is obtained via a linear Ginzburg-Landau model; the
effect of the wing trailing edge is accounted for by introducing a
semi-infinite half plane near the wavepacket; and the actuation is achieved by
placing a dipolar point source at the trailing edge, which models a
piezoelectric actuator. An optimal causal resolvent-based control method is
compared against the classical wave-cancellation method. The effect of the
causality constraint on the control performance is tested by placing the sensor
at different positions. We demonstrate that when the sensor is not positioned
sufficiently upstream of the trailing edge, which can be the case for the
actual control problem due to geometric restrictions, causality reduces the
control performance. We also show that this limitation can be moderated using
the optimal causal control together with modelling of the forcing.

Fluid Dynamics