نوع مقاله : مقاله پژوهشی
1 Associate Professor, Civil Engineering Department, Jundi-Shapur University of Technology, Dezful, Iran
2 Instructor in Civil Engineering Department Jundi-Shapur University of Technology, Dezful,Iran.
عنوان مقاله [English]
Flow aeration in chute spillway is one of the most effective and economic ways to prevent cavitation damage. Surface damage is significantly reduced when very small values of air are scattered in a water prism. A structure known as an aerator may be used for this purpose. Besides, ramp angle is one of the factors influencing aerator efficiency. In this research, the value of air entraining the flow through the Jarreh Dam’s spillway at the ramp angles of 6, 8 and 10 degrees, as three different scenarios, was simulated using the Flow-3D software. In order to validate the results of the inlet air into the flowing fluid at a ramp angle of 6 degrees, the observational results of the dam spillway physical model from the laboratory of TAMAB Company in Iran were used. According to the results, raising the ramp angle increases the inlet air to the water jet nappe, and a ten-degree ramp angle provides the best aeration efficiency. The Flow-3D model can also simulate the two-phase water-air flow on spillways, according to the results.
2- Bayon, A., Toro, J. P., Bombardelli, F. A., Matos, J., & López-Jiménez, P. A. (2018). Influence of VOF technique, turbulence model and discretization scheme on the numerical simulation of the non-aerated, skimming flow in stepped spillways. Journal of Hydro-Environment Research, 19, 137–149. https://doi.org/10.1016/j.jher.2017.10.002
3- Brethour, J. M., & Hirt, C. W. (2009). Drift Model for Two-Component Flows. Flow Science, Inc., FSI-09-TN83Rev, 1–7.
4- Chanson, H. (1989). Study of air entrainment and aeration devices. Journal of Hydraulic Research, 27(3), 301–319. https://doi.org/10.1080/00221688909499166
5- Dong, Z., Wang, J., Vetsch, D. F., Boes, R. M., & Tan, G. (2019). Numerical simulation of air-water two-phase flow on stepped spillways behind X-shaped flaring gate piers under very high unit discharge. Water (Switzerland), 11(10). https://doi.org/10.3390/w11101956
6- Flow-3D, V. 11. 2. (2017). User Manual. Flow Science Inc.: Santa Fe, NM, USA;
7- Hirt, C. W. (2003). Modeling Turbulent Entrainment of Air at a Free Surface. Flow Science, Inc., FSI-03-TN6, 1–9.
8- Hirt, C. W. (2016). Dynamic Droplet Sizes for Drift Fluxes. Flow Science, Inc., 1–10.
9- Hirt, C. W., & Nichols, B. D. (1981). Volume of fluid (VOF) method for the dynamics of free boundaries. Journal of Computational Physics, 39(1), 201–225. https://doi.org/10.1016/0021-9991(81)90145-5
10- Kherbache, K., Chesneau, X., Zeghmati, B., Abide, S., & Benmamar, S. (2017). The effects of step inclination and air injection on the water flow in a stepped spillway: A numerical study. Journal of Hydrodynamics, 29(2), 322–331. https://doi.org/10.1016/S1001-6058(16)60742-4
11- Kramer, M., & Chanson, H. (2019). Optical flow estimations in aerated spillway flows: Filtering and discussion on sampling parameters. Experimental Thermal and Fluid Science, 103, 318–328. https://doi.org/10.1016/j.expthermflusci.2018.12.002
12- Mahmoudian, Z., Baharvand, S., & Lashkarara, B. (2019). Investigating the Flow Pattern in Baffle Fishway Denil Type. Irrigation Sciences and Engineering (JISE), 42(3), 179–196.
13- Meireles, I. C., Bombardelli, F. A., & Matos, J. (2014). Air entrainment onset in skimming flows on steep stepped spillways: An analysis. Journal of Hydraulic Research, 52(3). https://doi.org/10.1080/00221686.2013.878401
14- Parsaie, A., & Haghiabi, A. H. (2019). Inception point of flow aeration on quarter-circular crested stepped spillway. Flow Measurement and Instrumentation, 69. https://doi.org/10.1016/j.flowmeasinst.2019.101618
15- Richardson, J. F., & Zaki W N. (1979). Sedimentation and Fluidisation. Part 1. Trans. Inst. Chem. Eng, 32, 35–53.
16- Shamloo, H., Hoseini Ghafari, S., & Kavianpour, M. (2012). Experimental study on the effects of inlet flows on aeration in chute spillway (Case study: Jare Dam, Iran). 10th International Congress on Advances in Civil Engineering, Middle East Technical University, Ankara, Turkey.
17- Wang, S. Y., Hou, D. M., & Wang, C. H. (2012). Aerator of stepped chute in Murum Hydropower Station. Procedia Engineering, 28, 803–807. https://doi.org/10.1016/j.proeng.2012.01.813.
18- Wei, W., Deng, J., & Zhang, F. (2016). Development of self-aeration process for supercritical chute flows. International Journal of Multiphase Flow, 79, 172–180. https://doi.org/10.1016/j.ijmultiphaseflow.2015.11.003
19- Wu, J., QIAN, S., & MA, F. (2016). A new design of ski-jump-step spillway. Journal of Hydrodynamics, 05, 914–917.
20- Xu, Y., Wang, W., Yong, H., & Zhao, W. (2012). Investigation on the cavity backwater of the jet flow from the chute aerators. Procedia Engineering, 31, 51–56. https://doi.org/10.1016/j.proeng.2012.01.989
21- Yakhot, V., & Orszag, S. A. (1986). Renormalization group analysis of turbulence. I. Basic theory. Journal of Scientific Computing, 1(1), 3–51. https://doi.org/10.1007/BF01061452
22- Yang, J., Teng, P., & Lin, C. (2019). Air-vent layouts and water-air flow behaviors of a wide spillway aerator. Theoretical and Applied Mechanics Letters, 9(2), 130–143. https://doi.org/10.1016/j.taml.2019.02.009
23- Zhang, G., & Chanson, H. (2016). Interaction between free-surface aeration and total pressure on a stepped chute. Experimental Thermal and Fluid Science, 74, 368–381. https://doi.org/10.1016/j.expthermflusci.2015.12.011