DOI QR코드

DOI QR Code

Hydrodynamic Calculation of Two-stage Weis-Fogh Type Water Turbine

2단 직렬 Weis-Fogh형 수차의 유체역학적 특성계산

  • Ro, Ki Deok (Dept. of Mechanical System Engineering, Gyeongsang Nat'l Univ.)
  • 노기덕 (경상대학교 기계시스템공학과)
  • Received : 2017.03.06
  • Accepted : 2017.04.19
  • Published : 2017.11.01

Abstract

In this study, a model of two-stage Weis-Fogh type water turbine model is proposed, the hydrodynamic characteristics of this water turbine model are calculated by the advanced vortex method. The basic conditions and the motion of each wing are the same as that of the single-stage model previously proposed by the same author. The two wings (NACA0010 airfoils) and both channel walls are approximated by source and vortex panels, and free vortices are introduced from the body surfaces. The distance between the front wing axis and the rear wing axis, and the phase difference between the motion of the two wings, which is in phase and out of phase are set as the calculation parameters. For each case, the unsteady flow fields, pressure fields, force coefficients, and efficiency of the two wings are calculated, and the hydrodynamic characteristics of the proposed water turbine model are discussed.

연구는 직렬 2단 Weis-Fogh형 수차모델을 제안하고, 이 수차모델의 유체역학적 특성을 개선 와법으로 수치계산한 것이다. 기본조건 및 각 날개의 움직임은 이전에 저자가 제안한 단단 수차모델에서와 같게 했다. 두 날개(NACA0010 airfoils) 및 양쪽 수로벽은 소스 및 볼텍스 판넬로 근사하였고, 자유볼텍스는 각 물체 표면 전체에서 도입하였다. 계산변수로는 앞날개와 뒷날개의 날개 축 사이의 거리 및 두 날개 운동의 위상차 즉 동위상과 역위상으로 했다. 각 경우에 대해 비정상 유동장 및 압력장 그리고 두 날개에 작용하는 힘의 계수 및 효율을 계산하였고, 이 수차모델의 유체역학적 특성을 논의하였다.

Keywords

References

  1. Weis-Fogh, T., 1973, "Quick Estimates of Flight Fitness in Hovering Animals, Including Novel Mechanism for Lift Production," Journal of Experimental Biology, Vol. 59, pp. 169-230.
  2. Lighthill, M. J., 1973, "On the Weis-Fogh Mechanism of Lift Generation," Journal of Fluid Mechanics, Vol. 60, Part1, pp. 1-17. https://doi.org/10.1017/S0022112073000017
  3. Maxworthy, T., 1979, "Experiments on the Weis-Fogh Mechanism of Lift Generation by Insects in Hovering Flight. Part 1. Dynamics of the 'Fling'," Journal of Fluid Mechanics, Vol. 93, pp. 47-63. https://doi.org/10.1017/S0022112079001774
  4. Edwards, R. H. and Cheng, H. K., 1982, "The Separation Vortex in the Weis-Fogh Circulation- Generation Mechanism," Journal of Fluid Mechanics, Vol. 120, pp. 463-473. https://doi.org/10.1017/S0022112082002857
  5. Spedding, G. R. and Maxworthy, T., 1986, "The Generation of Circulation and Lift in a Rigid Two-Dimensional Fling," Journal of Fluid Mechanics, Vol. 165, pp. 247-272. https://doi.org/10.1017/S0022112086003087
  6. Ro, K. D. and Tsutahara, M., 1997, "Numerical Analysis of Unsteady Flow in the Weis-Fogh Mechanism by the 3D Discrete Vortex Method with GRAPE3A," Journal of Fluids Engineering, Vol. 119, pp. 96-102. https://doi.org/10.1115/1.2819125
  7. Zhang, S. S., Wu, X. H. and Wang, X. F., 1999, "Research and Progress of Weis-Fogh Mechanism Hydrodynamics," Journal of Hydrodynamics, Vol. 3. pp. 55-60.
  8. Maxworthy, T., 2007, "The Formation and Maintenance of a Leading Edge Vortex During the Forward Motion of Animal Wing," Journal of Fluid Mechanics, Vol. 587, pp. 471-475.
  9. Kolomenskiy, D., Moffatt, H.K., Farge, M. and Schneider, K., 2011, "The Lighthill-Weis-Fogh Clapfling-sweep Mechanism Revisited," Journal of Fluid Mechanics, Vol. 676, pp. 573-606.
  10. Furber, S. B. and Ffowcs Williams, J. E., 1979, "Is the Weis-Fogh Principle Exploitable in Turbomachinary?," Journal of Fluid Mechanics, Vol. 94, Part 3, pp. 519-540. https://doi.org/10.1017/S0022112079001166
  11. Tsutahara, M. and Kimura, T., 1987, "An Application of the Weis-Fogh Mechanism to Ship Propulsion," Journal of Fluids Engineering, Vol. 109, pp. 107-113. https://doi.org/10.1115/1.3242629
  12. Tsutahara, M. and Kimura, T., 1987, "A Pilot Pump using the Weis-Fogh Mechanism and its Characteristics," Trans. Korean Soc. Mech. Eng. B, Vol. 54, No. 498, pp. 393-397.
  13. Tsutahara, M. and Kimura, T., 1994, "Study of a Fan Using the Weis-Fogh Mechanism(An Experimental Fan and Its Characteristics)," Trans. of the JSME(B), Vol. 60, No. 571, pp. 910-915. https://doi.org/10.1299/kikaib.60.910
  14. Ro, K.-D. and Seok, J.-Y., 2010, "Sailing Characteristics of a Model Ship of Weis-Fogh Type," Trans. Korean Soc. Mech. Eng. B, Vol. 34, No. 1, pp. 45-52. https://doi.org/10.3795/KSME-B.2010.34.1.45
  15. Ro, K. D., 2010, "Performance Improvement of Weis-Fogh Type Ship's Propulsion Mechanism Using a Wing Restrained by an Elastic Spring," Journal of Fluids Engineering, Vol. 132, No. 4, pp. 041101-1-041101-6. https://doi.org/10.1115/1.4001155
  16. Ro, K. D., 2012, "Numerical Calculation of Unsteady Flow Fields: Feasibility of Applying the Weis-Fogh Mechanism to Water Turbines," Journal of Fluids Engineering, Vol. 135, No. 10, pp. 101103-1-101103-6. https://doi.org/10.1115/1.4024956
  17. Ro, K. D., 2014, "Calculation of Hydrodynamic Characteristics of Weis-Fogh Type Water Turbine Using the Advanced Vortex Method," Trans. Korean Soc. Mech. Eng. B, Vol. 38, No. 3, pp. 203-210. https://doi.org/10.3795/KSME-B.2014.38.3.203
  18. Kamemoto, K., 1995, "On Attractive Features of the Vortex Methods, Computational Fluid Dynamics Review 1995," ed. M. Hafez and K. Oshima, JOHN WILEY& SONS, pp. 334-353.
  19. Ro, K. D., Zhu, B. S. and Kang, H. K., 2006, "Numerical Analysis of Unsteady Viscous Flow Through a Weis-Fogh Type Ship Propulsion Mechanism Using the Advanced Vortex Method," Journal of Fluids Engineering, Vol. 128, pp. 481-487. https://doi.org/10.1115/1.2174059
  20. Leonard, A., 1980, "Vortex Methods for Flow Simulations," Journal of Computational Physics, Vol. 37, pp. 289-335. https://doi.org/10.1016/0021-9991(80)90040-6
  21. Uhlman, J.S., 1992, "An Integral Equation Formulation of the Equation of Motion of an Incompressible Fluid," Naval Undersea Warfare Center T. R., pp. 10-86.
  22. Ro, K. D., 2014, "Experiments on Hydrodynamic Performance of Weis-fogh-type Water Turbine," Trans. of the CSME, Vol. 38, No. 3, pp. 405-415.