Development of Intelligent Jet Nozzle for Low-NOx High-Heat-Load Small Combustor

Overview Accompanied by the recent popularization of small-scale distributed energy system, further downsizing of combustors is expected. Such downsizing, however, may cause increase of NOx and intermittent instability of combustion due to poor mixing following the decrease of Reynolds number. Turbulent combustion is a phenomenon deeply related to the mixing/diffusion of heat, mass and momentum, and the chemical reaction at the molecular level. Therefore, drastic improvement of combustion characteristics is expected by actively controlling the fluid motion. In the present study, we develop intelligent nozzles, which can flexibly control the mixing state of air and fuel under low Reynolds number condition. So far, we succeeded to control the premixed flame in a small-scale combustor at a low Reynolds number by using an intelligent nozzle, which has arrayed micro-actuators fabricated by MEMS technique. Currently, analysis of exhaust gas, laser measurement such as OH/NO LIF and 3C-PIV, and large-scale numerical simulation are made in order to clarify the control effects and mixing mechanisms Based on that knowledge, we propose more flexible and effective combustion control methods. Sponsor: JST (CREST)

Active control of diffusion flame by intelligent nozzle: Measurement of concentration and velocity by PLIF/PIV DNS of actively controlled jet in a model combustor

Recent Reports

• Kasagi, N.,
  Keynote Lecture, "Toward Smart Control of Turbulent Jet Mixing and Combustion,"
  Proc. Int. Conf. Jets, Wakes and Separated Flows (ICJWSF-2005), Toba, JSME, Oct. 5-8, 2005, pp. 45-53.
  (PDF 1.5 Mbytes)

• Saiki, Y., Suzuki, Y., and Kasagi, N.,
  "The Structure of a Bluff-body Held Flame Controlled by Arrayed Micro Actuators,"
  Proc. 17th Int. Symp. Transport Phenomena, September 4-8, 2006, Paper No. 2-D-II-4
  (PDF 712 kbytes)

• Kurimoto, N., Suzuki, Y., and Kasagi, N.,
  "Active Control of Lifted Diffusion Flames with Arrayed Micro Actuators,"
  Exp. Fluids, Vol. 39, No. 6, (2005), pp. 995 - 1008.
  (doi:10.1007/s00348-005-0033-5)

• Angele, K. P., Kurimoto, N., Suzuki, Y., and Kasagi, N.,
  "Evolution of The Streamwise Vortices in a Coaxial Jet Controlled with Micro Flap-actuators,"
  J. Turbulence, Vol. 6, No. 73, (2006), 19 pp.
  (PDF 732 kbytes, doi:10.1080/14685240600983600 )

• Angele, K. P.,Kurimoto, N., Suzuki, Y., and Kasagi, N.,
  "Three-dimensional vortical structures in a coaxial jet manipulated with micro-actuators,"
  Proc. 6th World Conf. Experimental Heat Transfer, Fluid Mechanics and Thermodynamics, April 17-21, Matsushima, Japan (CD-ROM), Paper 9-b-10, 7 pp.
  (PDF 836 kbytes)

• Suzuki, H., Kasagi, N. and Suzuki, Y.,
  "Active control of an axisymmetric jet with distributed electromagnetic flap actuators,"
  Exp. Fluids, Vol. 36, pp. 498-509 (2004).
  (PDF 2.0 Mbytes, doi:10.1007/s00348-003-0756-0)

• Mitsuishi, A., Fukagata, K. and Kasagi, N.,
  "Near-field development of large-scale vortical structures in a controlled confined coaxial jet,"
  J. Turbulence, Vol. 8, No. 23, pp. 1-27 (2007).
  (PDF 2.0 Mbytes, doi:10.1080/14685240600871037)

• Mitsuishi, A., Fukagata, K., and Kasagi, N.,
  "On the relationship between large-scale vortical structure and scalar transport processes in a controlled confined coaxial jet,"
  Proc. 4th Int. Symp. Turbulence and Shear Flow Phenomena (TSFP-4), Williamsburg, Virginia, June 27-29, 2005, pp. 841-846.
  (PDF 1.0 Mbytes)

Last update: 2007-7-5