This study presents the application of the deep reinforcement learning (DRL) method in water tunnel experiments
which establishes an automatic closed-loop optimization framework in the laboratory. The framework is used to optimize the propulsion efficiency of a NACA0012 airfoil model under pure pitching motion at a Reynolds number of
Re
= 1.3×10
4
. Existing related studies often limit the motion patterns to periodic functions
thanks to the DRL method
the optimization process can take place in a broader non-periodic action space. In the experiment
the airfoil automatically interacts with the water tunnel environment
and ultimatel
y learns highly efficient non-periodic motions. By modifying the reward function
the efficiency optimization can be achieved above a given thrust threshold. The present findings demonstrate the DRL model can continuously enhance the propulsion efficiency by adjusting the amplitude and frequency of the flapping motion. Moreover
the optimal flapping motion obtained by DRL is close to the sinusoidal motion
and the achieved optimal propulsion efficiency lies on the upper bound of that of the sinusoidal motion with a similar amplitude. The present study demonstrates the feasibility of using the DRL method for complex flow control problems.
关键词
Keywords
references
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