R&D Study of Intelligent Active Turbulence-Control System

Overview Active feedback control of turbulence is attracting much attention in the fields of energy-related engineering and environmental science, because it has a great potential for flexible control fluid drag or heat and mass transfer, and enhancement/suppression of diffusion. In the present study, we perform R&D studies on such active feedback turbulence control from different perspectives, both on hardware and software components, in order to prove its principle in the labolatory experiments. Concerning the software components, we reproduce wall-bounded turbulent flows by using direct numerical simulation (DNS) and attempt to clarify their dynamics. We also develop efficient control algorithms by using the modern control theory and the genetic algorithm, and demonstrate the possibility of drag reduction based on the information measureable on the walls only. As for the hardware components, we develop a micro wall-shear stress sensor with very high dynamic response. Moreover, numerical analysis-based design-optimization lead to an even higher sensor response. We integrate these components into a system with arrayed sensor and deformable-membrane-type mangetic actuators placed in a matrix. Currently, we eveluate this system in order to experimentally prove the drag reduction of wall turbulence by the strategy we propose. Sponsor: SMART (MEXT), FY2000-04.

The Control System Prototype Arrayed MEMS Wall Shear Streess Sensors with Back-Side Wiring

Recent Reports

• Kasagi, N., Fukagata, K., and Suzuki, Y.,
  Plenary Lecture: "Toward feedback control of wall turbulence for skin friction,"
  Proc. Conf. on Active Flow Control, Berlin Germany, September 27-29, 2006 (CD-ROM), 19 pp.
  (PDF 3.5 Mbytes)

• Kasagi, N. and Fukagata, K.,
  "The FIK identity and its implication for turbulent skin friction control,"
  Transition and Turbulence Control, edited by M. Gad-el-Hak and H. M. Tsai (World Scientific, Singapore, 2006), Chapter 10, pp. 297-324.
  (Book info.)

• Suzuki, Y., Yoshino, T., Yamagami, T., and Kasagi, N.,
  "GA-based feedback control system for drag reduction in turbulent channel flow,"
  Proc. 4th Int. Symp. Turbulence and Shear Flow Phenomena (TSFP-4), Williamsburg, Virginia, June 27-29, 2005, pp. 301-306.
  (PDF 5.0 Mbytes).

• Yamagami, T., Suzuki, Y., and Kasagi, N.,
  "Development of feedback control system of wall turbulence using MEMS devices,"
  Proc. 6th Symp. Smart Control of Turbulence, March 6-9, 2005, Tokyo, pp. 135-141.
  (PDF 1.8 Mbytes).

• Yoshino, T., Suzuki, Y., Kasagi, N. and Kamiunten, S.,
  "Optimum Design of Micro Thermal Flow Sensor and Its Evaluation in Wall Shear Stress Measurement, "
  Proc. Int. Conf. MEMS'03, Jan. 2003, Kyoto, pp. 193-196.
  (PDF 788 kbyte).

• Pimpin, A., Suzuki, Y., and Kasagi, N.,
  "Micro electrostrictive actuator with metal compliant electrodes for flow control applications,"
  Proc. 17th IEEE Int. Conf. MEMS2004, Jan. 2004, Maastricht, pp. 478-481.
  (PDF 425 kbytes).

• Fukagata, K. and Kasagi, N.,
  "Feedback control of near-wall Reynolds shear stress in wall-turbulence"
  Proc. 4th Int. Symp. on Advanced Fluid Information and Transdisciplinary Fluid Integration, November 2004, Sendai, pp. 346-351.
  (PDF 180 kbytes).

• Fukagata, K., and Kasagi, N.,
  "Suboptimal control for drag reduction via suppression of near-wall Reynolds shear stress"
  Int. J. Heat Fluid Flow, Vol. 25, pp. 341-350 (2004).
  (PDF 849 kbytes, doi:10.1016/j.ijheatfluidflow.2004.02.015)

• Morimoto, K., Iwamoto, K., Suzuki, Y., and Kasagi, N.,
  "Genetic Algorithm-Based Optimization of Feedback Control Scheme for Wall Turbulence, "
  Proc. 3rd Symp. Smart Control of Turbulence, Mar. 2002, Tokyo, pp. 107-113.
  (PDF 3.6 Mbyte).

• Iwamoto, K., Kasagi, N., and Suzuki, Y.,
  "Direct numerical simulation of turbulent channel flow at Re_τ = 2320,"
  Proc. 6th Symp. Smart Control of Turbulence, March 6-9, 2005, Tokyo, pp. 327-333.
  (PDF 831 kbytes)

• Iwamoto, K., Fukagata, K., Kasagi, N., and Suzuki, Y.,
  "Friction drag reduction achievable by near-wall turbulence manipulation at high Reynolds numbers,"
  Phys. Fluids, Vol. 17, No. 011702 (2005).
  (PDF 329 kbytes, doi:10.1063/1.1827276)

• Iwamoto, K., Suzuki, Y., and Kasagi, N.,
  "Reynolds Number Effect on Wall Turbulence: Toward Effective Feedback Control,"
  Int. J. Heat and Fluid Flow, Vol. 23, pp. 678-689 (2002).
  (PDF 748 kbytes, doi:10.1016/S0142-727X(02)00164-9)
  Erratum (PDF 12 Kbyte, doi:10.1016/S0142-727X(02)00197-2

• Fukagata, K. and Kasagi, N.,
  "Drag Reduction in Turbulent Pipe Flow with Feedback Control Applied Partially to Wall,"
  Int. J. Heat Fluid Flow, Vol. 24, pp. 480-490 (2003).
  (PDF 335 kbytes, doi:10.1016/S0142-727X(03)00058-4)

• Fukagata, K., Kasagi, N., and Koumoutsakos, P.,
  "A theoretical prediction of friction drag reduction in turbulent flow by superhydrophobic surfaces,"
  Phys. Fluids, Vol. 18, No. 051703 (2006).
  (PDF 113 kbytes, doi:10.1063/1.2205307)

• Fukagata, K., Iwamoto, K. and Kasagi, N.,
  "Contribution of Reynolds Stress Distribution to the Skin Friction in Wall-Bounded Flows,"
  Phys. Fluids, Vol. 14, pp. L73-L76 (2002).
  (PDF 90 kbytes, doi:10.1063/1.1516779)

Last update: 2007-02-01