Please use this identifier to cite or link to this item: https://hdl.handle.net/1783.1/107418
Closed-loop control of a globally unstable jet using genetic programming
| Author |
Yang, Zhijian
Yin, Bo Guan, Yu Redonnet, Stephane Pierre Andre 
Zhu, Yuanhang Gupta, Vikrant Li, Larry K.B.
|
|---|---|
| Issue Date | 2020 |
| Abstract | When the density of a jet is sufficiently below that of its surroundings, it can become globally unstable, transitioning from a steady state to a self-excited state characterized by axisymmetric limit-cycle oscillations. We present experiments on the closed-loop control of such oscillations using an unsupervised data-driven model-free framework based on genetic programming (GP). Our implementation of this GP-based control framework relies on a hot-wire probe for sensing and a loudspeaker for actuation. We first initialize a generation of candidate control laws and evaluate their individual performance on the basis of a cost function that accounts for the amplitude of the global mode in a low-density jet and the actuation effort. We then breed further generations of control laws by enrolling them in a tournament and by executing genetic operations such as mutation, crossover, replication and elitism. By benchmarking the best GP-based control law against the best periodic forcing strategy found via conventional open-loop mapping, we show that GP-based control can provide a more efficient means of global mode suppression, offering new insight into the physics of hydrodynamically self-excited jets. |
| Conference | 73rd Annual Meeting of the American Physical Society’s Division of Fluid Dynamics (APS/DFD 2020), Virtual, 22-24 November 2020 |
| Language | English |
| Type | Conference paper |