Comparison of active flow control devices on bluff body shapes

Active flow control devices have been proven to reduce drag and delay stall on commercial aircraft. This leads to lower fuel usage and thus reduced flight costs. However, there is a large uncertainty as to how to integrate active flow control devices into aircraft, specifically those with composite structures. In addition, the cost of manufacturing active flow control devices for large-scale production has not been previously studied. In this article, design concepts for the attachment of a fluidic oscillator to a composite aircraft structure are investigated. A systematic approach from the conceptual design to the final design is performed using different design tools. A cost analysis is performed to select the most cost-effective design configuration based on large volume fluidic oscillator production. Through design validation and cost estimation, the final design is shown to be feasible for large volume manufacturing.

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CFD simulations of active flow control devices applied on a cambered flap

10.2514/6.2022-1545 ◽

2022 ◽

Author(s):

Abderahmane Marouf ◽

Dinh Hung Truong ◽

Yannick Hoarau ◽

Alain Gehri ◽

Dominique Charbonnier ◽

...

Keyword(s):

Flow Control ◽

Active Flow Control ◽

Cfd Simulations ◽

Flow Control Devices ◽

Control Devices ◽

Active Flow

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The Development of Active Flow Control Devices From Shape Memory Alloys for the Convective Cooling of Heated Surfaces

Volume 10: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A, B, and C ◽

10.1115/imece2008-68691 ◽

2008 ◽

Cited By ~ 1

Author(s):

Mohd S. Aris ◽

Ieuan Owen ◽

Chris J. Sutcliffe

Keyword(s):

Heat Transfer ◽

Flow Control ◽

Heated Surface ◽

Active Flow Control ◽

Control Device ◽

Flow Control Devices ◽

Flow Control Device ◽

Control Devices ◽

Channel Configuration ◽

Active Flow

This paper is concerned with the convective heat transfer of heated surfaces through the use of active flow control devices. An investigation has been carried out into the use of two flow control design configurations manufactured from Shape Memory Alloys (SMAs) which are activated at specified temperatures. In this design, a high surface temperature would activate rectangular flaps to change shape and protrude at a 45° angle of attack. This protrusion would generate longitudinal vortices and at the same time allow air to flow into cooling channels underneath the flaps, cooling a heated surface downstream of the flow control device. One- and two-channel flow control configurations were explored in this work. The flow control device was made from pre-alloyed powders of SMA material in a rapid prototyping process known as Selective Laser Melting (SLM). It was tested for its heat transfer enhancement in an open test section wind tunnel supplied with low velocity air flow. Infrared thermography was used to evaluate the surface temperatures of the downstream heated surface. Promising results were obtained for the flow control design when the heated surface temperatures were varied from 20 °C to 85 °C. In the one-channel configuration, the flow control device in its activated shape increased heat transfer to a maximum of 50% compared to its deactivated shape. The activated flow control device in the two-channel configuration experienced a heat transfer enhancement of up to 90% compared to when it is deactivated.

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CHOICE BETWEEN PASSIVE AND ACTIVE FLOW CONTROL DEVICES AT COMPLETING AN INTELLIGENT WELL

Actual Problems of Oil and Gas ◽

10.29222/ipng.2078-5712.2018-21.art7 ◽

2018 ◽

Author(s):

E.S. Zakirov ◽

S.N. Zakirov ◽

I.M. Indrupskiy ◽

D.P. Anikeev

Keyword(s):

Flow Control ◽

Active Flow Control ◽

Flow Control Devices ◽

Control Devices ◽

Active Flow

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Reinforcement learning for bluff body active flow control in experiments and simulations

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2004939117 ◽

2020 ◽

Vol 117 (42) ◽

pp. 26091-26098

Author(s):

Dixia Fan ◽

Liu Yang ◽

Zhicheng Wang ◽

Michael S. Triantafyllou ◽

George Em Karniadakis

Keyword(s):

Reinforcement Learning ◽

Fluid Mechanics ◽

Drag Reduction ◽

Flow Control ◽

Bluff Body ◽

Control Strategies ◽

Active Flow Control ◽

Reduction Process ◽

Automatic Sequence ◽

Active Flow

We have demonstrated the effectiveness of reinforcement learning (RL) in bluff body flow control problems both in experiments and simulations by automatically discovering active control strategies for drag reduction in turbulent flow. Specifically, we aimed to maximize the power gain efficiency by properly selecting the rotational speed of two small cylinders, located parallel to and downstream of the main cylinder. By properly defining rewards and designing noise reduction techniques, and after an automatic sequence of tens of towing experiments, the RL agent was shown to discover a control strategy that is comparable to the optimal strategy found through lengthy systematically planned control experiments. Subsequently, these results were verified by simulations that enabled us to gain insight into the physical mechanisms of the drag reduction process. While RL has been used effectively previously in idealized computer flow simulation studies, this study demonstrates its effectiveness in experimental fluid mechanics and verifies it by simulations, potentially paving the way for efficient exploration of additional active flow control strategies in other complex fluid mechanics applications.

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