Flow, Turbulence and Combustion

, Volume 81, Issue 1–2, pp 321–336 | Cite as

Promotion of Turbulent Thermal Mixing of Hot and Cold Airflows in T-junction

  • M. Hirota
  • M. Kuroki
  • H. Nakayama
  • H. Asano
  • S. Hirayama
Article
First Online:
Received:
Accepted:

Abstract

An experimental study has been conducted on the promotion and control of turbulent thermal mixing of hot and cold airflows in a T-junction with rectangular cross sections, which simulates the HVAC unit for automobile air-conditioning system. In order to promote the turbulent thermal mixing, small jets have been blown into the main channel at the upstream edge of the T-junction in the direction of 45° against the main flow. Turbulence intensity in the upper part of the thermal mixing layer can be increased with these jets, and consequently the turbulent mixing of hot and cold airflows is promoted effectively. Moreover, it has been found that the degree of thermal mixing can be controlled by changing the jet velocity.

Keywords

Turbulent mixing Mixing promotion T-junction HVAC Jet 
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Bruecker, C.: Study of the three-dimensional flow in a T-junction using a dual-scanning method for Three-Dimensional Scanning-Particle-Image-Velocimetry (3-D SPIV). Exp. Therm. Fluid Sci. 14, 35–44 (1997)CrossRefGoogle Scholar
  2. 2.
    Igarashi, M., Tanaka, M., Kawashima, S., Kamide, H.: Experimental study on fluid mixing for evaluation of thermal striping in T-pipe junction. Proc. 10th Int. Conf. Nuclear Eng. ICONE10-22255 (2002)Google Scholar
  3. 3.
    Kawamura, T., Shiina, K., Ohtsuka, K.M., Tanaka, I., Hirayama, H., Tanimoto, K., Fukuda, T., Sakashita, A., Mizutani, J., Minami, Y., Moriya, S., Madarame, H.: Experimental study on thermal striping in a mixing tee with hot and cold water. Proc. 10th Int. Conf. Nuclear Eng. ICONE10-22214 (2002)Google Scholar
  4. 4.
    Wu, H.L., Peng, X.F., Chen, T.K.: Influence of sleeve tube on the flow and heat transfer behavior at a T-junction. Int. J. Heat Mass Transfer 46:2637–2644 (2003)CrossRefGoogle Scholar
  5. 5.
    Fukushima, N., Fukagata, K., Kasagi, N., Noguchi, H., Tanimoto, K.: Numerical and Experimental Study on Turbulent Thermal Mixing in a T-junction Flow. Proc. 6th ASME–JSME Joint Thermal Eng. Conf., TED-AJ03-582, in CD-ROM (2003)Google Scholar
  6. 6.
    Kitada, M., Asano, H., Kanbara, M., Akaike, S.: Development of automotive air-conditioning system basic performance simulator: CFD technique development. JSAE Review 21:91–96 (2000)CrossRefGoogle Scholar
  7. 7.
    Asano, H., Hirota, M., Nakayama, H., Asano, T., Hirayama, S.: Experimental study on turbulent flow and thermal mixing in T-junction modeled after automobile HVAC unit. Proc. ASME Summer Heat Transfer Conf, HT2005-72478, in CD-ROM (2005)Google Scholar
  8. 8.
    Hirota, M., Asano, H., Nakayama, H., Asano, T., Goto, H., Hirayama, S.: Turbulent thermal mixing of hot and cold airflows in T-junction. Proc. 13th Int. Heat Transfer Conf., TRB-11, in CD-ROM (2006)Google Scholar
  9. 9.
    Kaehler, C.J., Sammler, B., Kompenhans, J.: Generation and control of tracer particles for optical flow investigation in air. Exp. Fluids 33:736–742 (2002)Google Scholar
  10. 10.
    Raffel, M., Willert, C., Kompenhans, J.: Particle Image Velocimetry, pp. 129–134. Springer, Berlin (1998)Google Scholar
  11. 11.
    Scarano, F.: Iterative image deformation methods in PIV. Meas. Sci. Technol. 13:R1–R19 (2002)CrossRefADSGoogle Scholar
  12. 12.
    Su, L.K., Mungal, M.G.: Simultaneous measurements of scalar and velocity field evolution in turbulent crossflowing jets. J. Fluid Mech. 513:1–45 (2004)MATHCrossRefADSGoogle Scholar
  13. 13.
    Nakajima, N., Hibara, H., Muramatsu, T., Tanaka, M., Iwamoto, Y., Ochi, J.: Effects of turbulence promoter on flow in T-junction piping system. Proc. Int. Conf. Jets, Wakes and Separated Flows :617–622 (2005)Google Scholar
  14. 14.
    Muppidi, S., Mahesh, K.: Direct numerical simulation of round turbulent jets in crossflow. J. Fluid Mech. 574:59–84 (2007)MATHCrossRefADSGoogle Scholar
  15. 15.
    Wegner, B., Huai, Y., Sadiki, A.: Analysis of the turbulent mixing in counterflow and jet in cross-flow configuration. In: Hanjalic, K., Nagano, Y., Tummers, M.J. (eds.) 4th Int. Symp. Turbulence Heat and Mass Transfer, pp. 903–910 (2003)Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • M. Hirota
    • 1
  • M. Kuroki
    • 2
  • H. Nakayama
    • 3
  • H. Asano
    • 4
  • S. Hirayama
    • 4
  1. 1.Department of Micro-Nano Systems EngineeringNagoya UniversityNagoyaJapan
  2. 2.Department of Mechanical EngineeringNagoya UniversityNagoyaJapan
  3. 3.Fuel Cell LaboratoryDaido Institute of TechnologyNagoyaJapan
  4. 4.Air-Conditioning Testing and Evaluation DepartmentDENSO CORPORATIONKariyaJapan

Personalised recommendations