Authors

1 Department of Mechanical Engineering .Tarbiat Modares University

2 Department of Mechanical Engineering, Tarbiat Modares University

3 Aerospace Science and Technology Research Institute, Aerospace Research Institute, Ministry of Science, Research and Technology

Abstract

Butterfly valves as control valves are used when a small pressure drop is required in the valve. The results of numerical studies of solving the incompressible flow equations around the butterfly valve in three dimensions are presented in this paper. ANSYS CFX commercial software is used to solve the flow equations. The ε-k turbulence model is used to simulate flow disturbances. Velocity, pressure distribution, kinetic energy, and turbulence intensity profiles are the factors that provide flow characteristics. The position of the disk at the opening angles of 0˚, 15˚, 30˚, 45˚, 60˚, and 75˚ as well as the inlet velocities of 1, 2, and 3 m/s have been investigated. Torque and valve performance factors such as flow coefficient and Hydrodynamics torque coefficient have been calculated for these different opening angles. The results of this simulation have been compared with the available experimental results for validation. The results show that the pressure drop across the valve, the flow coefficient, and the hydrodynamic torque coefficient depend on the opening angle. As the opening angle increases, the flow coefficient and the hydrodynamic torque coefficient decrease, and the torque and pressure drop increase across the valve. Flow separation has also been investigated at the mentioned opening angles.

Keywords

Article Title [Persian]

Simulation and Examination of Flow Characteristics of the Butterfly Valve

Authors [Persian]

  • Fathollah Ommi 1
  • Hamidreza Khodayari 2
  • Zoheir Saboohi 3

1 Department of Mechanical Engineering .Tarbiat Modares University

2 Department of Mechanical Engineering, Tarbiat Modares University

3 Aerospace Science and Technology Research Institute, Aerospace Research Institute, Ministry of Science, Research and Technology

Abstract [Persian]

Butterfly valves as control valves are used when a small pressure drop is required in the valve. The results of numerical studies of solving the incompressible flow equations around the butterfly valve in three dimensions are presented in this paper. ANSYS CFX commercial software is used to solve the flow equations. The ε-k turbulence model is used to simulate flow disturbances. Velocity, pressure distribution, kinetic energy, and turbulence intensity profiles are the factors that provide flow characteristics. The position of the disk at the opening angles of 0˚, 15˚, 30˚, 45˚, 60˚, and 75˚ as well as the inlet velocities of 1, 2, and 3 m/s have been investigated. Torque and valve performance factors such as flow coefficient and Hydrodynamics torque coefficient have been calculated for these different opening angles. The results of this simulation have been compared with the available experimental results for validation. The results show that the pressure drop across the valve, the flow coefficient, and the hydrodynamic torque coefficient depend on the opening angle. As the opening angle increases, the flow coefficient and the hydrodynamic torque coefficient decrease, and the torque and pressure drop increase across the valve. Flow separation has also been investigated at the mentioned opening angles.

Keywords [Persian]

  • Butterfly Valve
  • Hydrodynamic Torque Coefficient
  • Flow Coefficient
  • Turbulence
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