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This study introduces a new reinforcement learning (RL) algorithm for active flow control. It efficiently manages complex viscous flows using fewer system observations, improving stability and performance.

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Area of Science:

  • Fluid dynamics
  • Control theory
  • Machine learning

Background:

  • Reinforcement learning (RL) typically requires extensive system observations for active control problems.
  • Viscous flow systems, despite potentially low-dimensional dynamics, necessitate numerous observables in standard RL frameworks.
  • Partial observability in RL is challenging, often requiring full system state information.

Purpose of the Study:

  • To develop a consistent reinforcement learning algorithm for active flow control under partial observability.
  • To leverage the low-dimensional properties of viscous flow systems for improved RL efficiency.
  • To demonstrate a more stable and efficient RL approach compared to existing methods in flow control.

Main Methods:

  • Constructed a novel RL algorithm tailored for partially observable viscous flow systems.
  • Utilized the inherent low-dimensional state-space characteristics of viscous flows.
  • Tested the algorithm on typical active flow control scenarios.

Main Results:

  • The proposed RL algorithm demonstrated enhanced stability and efficiency.
  • The algorithm performed effectively even with a limited number of system observables.
  • Outperformed existing RL algorithms in active flow control tasks.

Conclusions:

  • The developed RL algorithm successfully addresses partial observability in viscous flow control.
  • Leveraging low-dimensional system properties enables efficient and stable flow control with minimal observables.
  • This approach offers a promising alternative for complex fluid dynamics control problems.