Advertisement

RESEARCH ON TRANSITIONAL FLOW CHARACTERISTICS OF LABYRINTHCHANNEL EMITTER

  • Wanhua Zhao
  • Jun Zhang
  • Yiping Tang
  • Zhengying Wei
  • Bingheng Lu
Conference paper
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT, volume 294)

Abstract

A physical model for flow characteristics analysis of labyrinth-channel emitter is reconstructed by Reverse Engineering from an injection molded part, and both laminar flow and turbulence models are adopted to simulate the flow state under the condition of low Reynolds numbers. According to the distribution of separation and reattachment points, the onset of transition from laminar to turbulent flow in labyrinth channels occurs at a range of Re=250~300. Furthermore, a visualization system of the flow field inside the labyrinth experiments. The experiment of tracing particles verifies the calculated flow field distribution, and another experiment using dyeing liquor showed the critical Reynolds number characterizing the transition, which is reasonably consistent with numerical simulation results. The critical Reynolds number obtained shows the fact that the flow inside this emitter is turbulent under the pressures of 40~150 kPa.

Keywords

Reynolds Number Turbulence Model Critical Reynolds Number Reynolds Stress Model Hydraulic Performance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. A. Q. Mohammad, Y J Jang, H C Chen, . Flow and heat transfer in rotating two-pass rectangular channels(AR=2) by Reynolds stress turbulence model. International Journal of Heat and Mass Transfer, 2002, 45: 1823–1838CrossRefMATHGoogle Scholar
  2. Fan Jichuan. Flow visualization technology in recently years. Beijing: National Defence Industry Press, 2002 (in Chinese)Google Scholar
  3. Song Kang, Zhao Yulong, Jiang Zhuangde, . Laser profilometer. Optics and Precision Engineering, 2003, 11(3): 245–248 (in Chinese)Google Scholar
  4. T. A. Rush, T. A. Newell, A. M. Jacobi. An experimental study of flow and heat transfer in sinusoidal wavy passages. International Journal of Heat and Mass Transfer, 1999, 42: 1541–1553CrossRefGoogle Scholar
  5. T. Nishimura, S. Murakami, S. Arakawa, . Flow observations and mass transfer characteristics in symmetrical wavy-walled channels at moderate Reynolds numbers for steady flow. International Journal of Heat and Mass Transfer, 1990, 33: 835–845CrossRefGoogle Scholar
  6. T. Nishimura, Y. Ohori, Y. Kawamura. Flow characteristics in a channel with symmetric wavy wall for steady flow. Journal of Chemical Engineering of JAPAN, 1984, 17: 466–471CrossRefGoogle Scholar
  7. Tao Wenquan. Numerical Heat Transfer (2nd edition). Xi'an: Xi'an Jiaotong University Press. 2001 (in Chinese)Google Scholar
  8. Wang Ruihuan, Zhao Wanhua, Yang Laixia, . Experimental study of the water-saving emitter structure based on rapid prototyping. Journal of Xi'an Jiaotong University, 2003, 37: 542–545 (in Chinese)Google Scholar
  9. Wei Qingsong, Shi Yusheng, Dong Wenchu, . Study on hydraulic performance of drip emitters by computational fluid dynamics. Agricultural Water Management, 2006, 84: 130–136CrossRefGoogle Scholar
  10. Yao Bin, Liu Zhifeng, Zhang Jianping. Study on the influence of channel length on dripper hydraulic performance. Water Saving Irrigation, 2003, (5): 38–39 (in Chinese)Google Scholar
  11. Zhang Jun, Zhao Wanhua, Lu Bingheng . Numerical and experimental study on hydraulic performance of emitters with arc labyrinth channels. Computers and Electronics in Agriculture, 2007, 56:120–129CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Wanhua Zhao
    • 1
  • Jun Zhang
    • 1
  • Yiping Tang
    • 1
  • Zhengying Wei
    • 1
  • Bingheng Lu
    • 1
  1. 1.Xi’an Jiaotong University, Xi’anShaanxi ProvinceChina

Personalised recommendations