Book contents
- Flow Control Techniques and Applications
- Cambridge Aerospace Series
- Flow Control Techniques and Applications
- Copyright page
- Contents
- Preface
- 1 Introduction
- 2 Gurney Flap
- 3 Vortex Generator
- 4 Roughness
- 5 Polymer
- 6 Biological Techniques
- 7 Jet
- 8 Synthetic Jet
- 9 Plasma Actuator
- 10 Lorentz Force
- 11 Closed-Loop Control
- Index
- References
10 - Lorentz Force
Published online by Cambridge University Press: 14 December 2018
Book contents
- Flow Control Techniques and Applications
- Cambridge Aerospace Series
- Flow Control Techniques and Applications
- Copyright page
- Contents
- Preface
- 1 Introduction
- 2 Gurney Flap
- 3 Vortex Generator
- 4 Roughness
- 5 Polymer
- 6 Biological Techniques
- 7 Jet
- 8 Synthetic Jet
- 9 Plasma Actuator
- 10 Lorentz Force
- 11 Closed-Loop Control
- Index
- References
Summary
Lorentz force is a novel active flow control device originating from electromagnetism. It can be generated in electric fluids with a specific arrangement of the electrodes and magnets, with forcing in either the streamwise or the spanwise direction. The Lorentz force can change its magnitude and direction periodically, and the boundary layer can therefore be changed with the generation of the near wall jet. Though streamwise Lorentz force may increase the friction drag of the boundary layer, spanwise Lorentz force could result in a considerable drag reduction up to about 40% for the turbulent boundary layer. It is found that periodic Lorentz force could induce spanwise vortices that might weaken the turbulence activities. In addition, Lorentz force could reduce the flow separation, thus it can increase the lift coefficient over airfoils and also reduce the lift fluctuation of a circular cylinder. Considering that electric fluids are required for the application of the Lorentz force, it is suitable for the flow control of sea vehicles, such as drag reduction in submarines.
- Type
- Chapter
- Information
- Flow Control Techniques and Applications , pp. 246 - 265Publisher: Cambridge University PressPrint publication year: 2018
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