0
Research Papers: Flows in Complex Systems

Vector Control of Synthetic Jets Using an Asymmetric Slot

[+] Author and Article Information
Ryota Kobayashi

Graduate School of Engineering,
Kogakuin University,
1-24-2, Nishishinjuku,
Shinjuku 163-8677, Tokyo, Japan
e-mail: am16027@ns.kogakuin.ac.jp

Koichi Nishibe

Mem. ASME
Department of Mechanical Engineering,
Tokyo City University,
1-28-1, Tamazutumi,
Setagaya 158-8557, Tokyo, Japan
e-mail: knishibe@tcu.ac.jp

Yusuke Watabe

Graduate School of Engineering,
Kogakuin University,
1-24-2, Nishishinjuku,
Shinjuku 163-8677, Tokyo, Japan
e-mail: yusukew.3a91@gmail.com

Kotaro Sato

Department of Mechanical System Engineering,
Kogakuin University,
1-24-2, Nishishinjuku,
Shinjuku 163-8677, Tokyo, Japan
e-mail: at12164@ns.kogakuin.ac.jp

Kazuhiko Yokota

Mem. ASME
Department of Mechanical Engineering,
Aoyama Gakuin University,
Sagamihara 252-5258, Kanagawa, Japan
e-mail: yokota@me.aoyama.ac.jp

1Corresponding author.

Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received April 11, 2017; final manuscript received September 22, 2017; published online January 9, 2018. Assoc. Editor: Riccardo Mereu.

J. Fluids Eng 140(5), 051102 (Jan 09, 2018) (11 pages) Paper No: FE-17-1223; doi: 10.1115/1.4038660 History: Received April 11, 2017; Revised September 22, 2017

This paper presents a fundamental study on jet vectoring control by adjusting the dimensionless frequency of synthetic jets over time without changing the injection nozzle shape in actuators. This work involves the introduction of asymmetric slots with various sharp projection lengths in free synthetic jets for various actuator frequencies. The influences of the dimensionless parameters, sharp projection length C, and actuator frequency f* on the behavior of free synthetic jets are experimentally investigated under the same slot width b and Reynolds number Re = 990, and numerical simulations are performed to supplement these experiments. Furthermore, the behavior of synthetic jets is compared with that of continuous jets. The measurements of the velocities for both jet types are performed for the flow visualizations to observe the jet behaviors obtained using the smoke-wire method. The typical flow patterns and the time-averaged velocity distributions of the synthetic jets for various sharp projection lengths and dimensionless frequencies are demonstrated through the experiment. The influence of the dimensionless frequency on the stagnation point near a rigid wall when the inclined synthetic jets form a recirculation flow is also investigated. Furthermore, the degree of the bend of the jets is evaluated based on the change in the jet center's position at a reference downstream cross section. The results show that the jet direction of the synthetic jets induced by the asymmetric slots is related to both the dimensionless sharp projection length and the dimensionless frequency.

FIGURES IN THIS ARTICLE
<>
Copyright © 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Holman, R. , Utturkar, Y. , Mittal, R. , Smith, B. L. , and Cattafesta, L. , 2005, “ Formation Criterion for Synthetic Jets,” AIAA J., 43(10), pp. 2110–2116. [CrossRef]
Smith, B. L. , and Swift, G. W. , 2003, “ A Comparison Between Synthetic Jets and Continuous Jets,” Exp. Fluids, 34(4), pp. 467–472. [CrossRef]
Nishibe, K. , Fujita, Y. , Sato, K. , Yokota, K. , and Koso, T. , 2011, “ Experimental and Numerical Study on the Flow Characteristics of Synthetic Jets,” J. Fluid. Sci. Tech., 6(4), pp. 425–436. [CrossRef]
Koso, T. , and Morita, M. , 2014, “ Effects of Stroke and Reynolds Number on Characteristics of Circular Synthetic Jets,” J. Fluid. Sci. Tech., 9(2), pp. 1–15. [CrossRef]
Koso, T. , Matsuda, S. , Masuda, H. , and Akahoshi, T. , 2014, “ Effect of Stroke on Structure of Vortex Ring Array in Circular Synthetic Jets,” J. Fluid. Sci. Tech., 9(3), pp. 1–11. [CrossRef]
Zhang, P. F. , and Wang, J. J. , 2007, “ Novel Signal Pattern for Efficient Synthetic Jet Generation,” AIAA J., 45(5), pp. 1058–1065. [CrossRef]
Nishibe, K. , Fujiwara, T. , Ohue, H. , Takezawa, H. , Sato, K. , and Yokota, K. , 2014, “ Synthetic Jet Using Bubbles Produced by Electric Discharge,” J. Fluid. Sci. Tech., 9(3), pp. 1–12. [CrossRef]
Feero, M. A. , Lavoie, P. , and Sullivan, P. E. , 2015, “ Influence of Cavity Shape on Synthetic Jet Performance,” Sens. Actuators A Phys., 223, pp. 1–10. [CrossRef]
Albright, S. O. , and Solovitz, S. A. , 2016, “ Examination of a Variable-Diameter Synthetic Jet,” ASME J. Fluid. Eng., 138(12), p. 121103. [CrossRef]
Amitay, M. , Smith, D. , Kibens, V. , Parekh, D. , and Glezer, A. , 2001, “ Aerodynamic Flow Control Over an Unconventional Airfoil Using Synthetic Jet Actuators,” AIAA J., 39(3), pp. 361–370. [CrossRef]
Haider, B. A. , Durrani, N. , Aizud, N. , and Zahir, S. , 2010, “ Aerodynamic Stall Control of a Generic Airfoil Using Synthetic Jet Actuator,” World Acad. Sci. Eng. Technol., 4(9), pp. 117–122. http://waset.org/publications/14806/aerodynamic-stall-control-of-a-generic-airfoil-using-synthetic-jet-actuator
Yen, J. , and Ahmed, N. A. , 2012, “ Parametric Study of Dynamic Stall Flow Field With Synthetic Jet Actuation,” ASME J. Fluid. Eng., 134(7), p. 071106. [CrossRef]
Duvigneau, R. , Hay, A. , and Visonneau, M. , 2007, “ Optimal Location of a Synthetic Jet on an Airfoil for Stall Control,” ASME J. Fluid. Eng., 129(7), pp. 825–833. [CrossRef]
McGuinn, A. , Farrelly, R. , Persoons, T. , and Murray, D. B. , 2013, “ Flow Regime Characterization of an Impinging Axisymmetric Synthetic Jet,” Exp. Therm. Fluid Sci., 47, pp. 241–251. [CrossRef]
Trávníček, Z. , Němcová, L. , Kordík, J. , Tesař, V. , and Kopecky´, V. , 2012, “ Axisymmetric Impinging Jet Excited by a Synthetic Jet System,” Int. J. Heat Mass Transf., 55(4), pp. 1279–1290. [CrossRef]
Al-Atabi, M. , 2011, “ Experimental Investigation of the Use of Synthetic Jets for Mixing in Vessels,” ASME J. Fluid. Eng., 133(9), p. 094503. [CrossRef]
Xia, Q. , and Zhong, S. , 2012, “ A PLIF and PIV Study of Liquid Mixing Enhanced by a Lateral Synthetic Jet Pair,” Int. J. Heat Fluid Flow, 37, pp. 64–73. [CrossRef]
Chaudharia, M. , Puranika, B. , and Agrawal, A. , 2010, “ Effect of Orifice Shape in Synthetic Jet-Based Impingement Cooling,” Exp. Therm. Fluid. Sci., 34(2), pp. 246–256. [CrossRef]
Chiekh, M. B. , Ferchichi, M. , and Béra, J. C. , 2012, “ Aerodynamic Flow Vectoring of a Wake Using Asymmetric Synthetic Jet Actuation,” Exp. Fluid., 53(6), pp. 1797–1813. [CrossRef]
Chiekh, M. B. , Ferchichi, M. , and Béra, J. C. , 2011, “ Modified Flapping Jet for Increased Jet Spreading Using Synthetic Jets,” Int. J. Heat Fluid Flow, 32(5), pp. 865–875. [CrossRef]
Feng, L. H. , Wang, J. J. , and Pan, C. , 2010, “ Effect of Novel Synthetic Jet on Wake Vortex Shedding Modes of a Circular Cylinder,” J. Fluid. Struct., 26(6), pp. 900–917. [CrossRef]
Feng, L. H. , and Wang, J. J. , 2010, “ Circular Cylinder Vortex-Synchronization Control With a Synthetic Jet Positioned at the Rear Stagnation Point,” J. Fluid. Mech., 662, pp. 232–259. [CrossRef]
Smith, B. L. , and Glezer, A. , 2002, “ Jet Vectoring Using Synthetic Jets,” J. Fluid. Mech., 458, pp. 1–34. [CrossRef]
Luo, Z. B. , Xia, Z. X. , and Xie, Y. G. , 2007, “ Jet Vectoring Control Using a Novel Synthetic Jet Actuator,” Chin. J. Aeronaut., 20(3), pp. 193–201. [CrossRef]
Smith, B. L. , and Glezer, A. , 2005, “ Vectoring of Adjacent Synthetic Jets,” Aiaa J., 43(10), pp. 2117–2124. [CrossRef]
Pavlova, A. A. , Otani, K. , and Amitay, M. , 2008, “ Active Control of Sprays Using a Single Synthetic Jet Actuator,” Int. J. Heat Fluid Flow, 29(1), pp. 131–148. [CrossRef]
Watabe, Y. , Sato, K. , Nishibe, K. , and Yokota, K. , 2016, “ Influence of an Asymmetric Slot on the Flow Characteristics of Synthetic Jets,” Springer Proc. Phys., 185, pp. 101–107. [CrossRef]
Tang, H. , and Zhong, S. , 2005, “ 2D Numerical Study of Circular Synthetic Jets in Quiescent Flows,” Aeronaut. J., 109(1092), pp. 89–97. [CrossRef]
Rizzetta, D. , Visbal, M. , and Stanek, M. , 1999, “ Numerical Investigation of Synthetic Jet Flow Fields,” AIAA J., 37(8), pp. 919–927. [CrossRef]
Kiwata, T. , Kimura, S. , Komatsu, N. , Murata, H. , and Kim, Y. H. , 2009, “ Flow Characteristics of a Plane Jet With an Extended Lip-Plate and Serrated Tabs,” J. Fluid. Sci. Tech., 4(2), pp. 268–278. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Schematic drawing of the experimental apparatus: synthetic and continuous jets generated by the speaker and the blower, respectively

Grahic Jump Location
Fig. 2

Geometric shape of an asymmetric slot. The asymmetric slot is obtained by applying a sharp projection to the edge of the slot.

Grahic Jump Location
Fig. 3

Domain and boundary conditions for the numerical simulations of the synthetic jets with the asymmetric slot. The divergence of the results is avoided by supplying 5% of the characteristic velocity from the upper and lower bounds. For simplicity, a sine wave is used to describe the velocity change of the synthetic jet at the slot.

Grahic Jump Location
Fig. 4

Flow patterns of the continuous jets (Uc0 = 3.0 m/s; Re = 990). The exposure time is 0.1 s. The sharp projection is indicated by triangles: (a) smoke-wire method, (b) numerical simulation, and (c) mean velocity distribution by hot-wire.

Grahic Jump Location
Fig. 5

Typical flow patterns of the synthetic jets produced by the asymmetric slot (f* = 2.50 × 10−2; f = 20 Hz; Uc0 = 3.0 m/s; Re = 990). The cross markers are plotted on the newly generated clockwise vortex. The +Γ and −Γ vortices are generated in different x-directional positions and move to the bottom right-hand corner of the diagrams. The suction fluid has a significant effect on the −Γ vortex: (a) smoke-wire method, (b) vorticity distribution, and (c) velocity vectors.

Grahic Jump Location
Fig. 6

Flow patterns of the synthetic jets (f* = 5.00 × 10−2; f = 30 Hz; Us0 = 3.0 m/s; Re = 990). The exposure time is 0.1 s. The sharp projection is indicated by triangles. The curvature of the synthetic jets increases with respect to the increases in the dimensionless sharp projection length C: (a) smoke-wire method, (b) numerical simulation, and (c) mean velocity distribution by hot-wire.

Grahic Jump Location
Fig. 7

Flow patterns of the synthetic jets (f* = 1.67 × 10−2; f = 10 Hz; Us0 = 3.0 m/s; Re = 990). The exposure time is 0.1 s. The sharp projection is indicated by triangles. The synthetic jet for f* = 1.67 × 10−2 in the asymmetric slot in (ii) C = 3 and (iii) C = 5 proceeds to be approximately straight than that in f* = 5.00 × 10−2: (a) smoke-wire method, (b) numerical simulation, and (c) mean velocity distribution by hot-wire.

Grahic Jump Location
Fig. 8

Mean velocity distributions in the vicinity of a rigid wall by LDV for various values of the dimensionless frequency f* (C = 3; Us0 = 3.0 m/s; x/b0 = 1; Re = 990). The y/b0 point, where the tangential velocity should be zero, is defined as the stagnation point on the rigid wall.

Grahic Jump Location
Fig. 9

LDV measurement of the stagnation point near the wall surface (C = 3; Us0 = 3.0 m/s; x/b0 = 1 and z/b0 = 0; Re = 990). The stagnation point is where the tangential velocity is zero. The cross markers are plotted at yst/b0 = −74 (the position of the wall's end) if no stagnation points are present on the wall. The jet curvature of the synthetic jets increases, and the size of the recirculation region becomes smaller with an increasing dimensionless frequency f* under the same dimensionless sharp projection length C.

Grahic Jump Location
Fig. 10

Contour map of the jet center position evaluated by the x-component velocity distributions measured by the hot-wire anemometer at x/b0 = 10 (Us0 = 3.0 m/s; Re = 990). Both the dimensionless sharp projection length C and the dimensionless frequency f* affect the change in the jet center position. Therefore, the jet flow direction can be controlled by adjusting the dimensionless sharp projection length and/or the dimensionless frequency.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In