Investigation of the Effect of Ramp Angle on Chute Aeration System Efficiency by Two-Phase Flow Analysis

نوع مقاله : مقاله پژوهشی

نویسندگان

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.

چکیده

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.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of the Effect of Ramp Angle on Chute Aeration System Efficiency by Two-Phase Flow Analysis

نویسندگان [English]

  • Babak Lashkar-Ara 1
  • Leila Najafi 2
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.
چکیده [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.

کلیدواژه‌ها [English]

  • Aeration system
  • Ramp angle
  • Aeration coefficient
  • Two-Phase Flow
  • Flow-3D model
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