An Experimental Investigation of Butterfly Valve Performance Downstream of an Elbow

The results of an experimental investigation concerning the operating characteristics of a butterfly valve downstream of a mitered elbow are reported. Primary emphasis is given the influences of valve disk angle, valve/elbow spacing, and valve/elbow orientation on the dimensionless pressure drop, mass flow coefficient, and aerodynamic torque coefficient characteristics of the valve. The results show that when the valve is located two pipe diameters downstream of the elbow, the performance characteristics are substantially affected by the relative valve/elbow orientation. However, at a spacing of eight diameters the effect of the elbow on the valve operating characteristics is small.

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The Performance of Two Butterfly Valves Mounted in Series

Journal of Fluids Engineering ◽

10.1115/1.2909512 ◽

1991 ◽

Vol 113 (3) ◽

pp. 419-423 ◽

Cited By ~ 9

Author(s):

M. J. Morris ◽

J. C. Dutton

Keyword(s):

Experimental Investigation ◽

Pressure Drop ◽

System Performance ◽

Combined Effect ◽

Operating Characteristics ◽

Dimensionless Pressure ◽

Mass Flowrate ◽

In Series ◽

Torque Coefficient ◽

Aerodynamic Torque

The results of an experimental investigation concerning the operating characteristics of two similar butterfly valves mounted in series are reported. Emphasis is given to the influence of the upstream valve disk angle, the downstream valve disk angle, the relative valve orientation, and the spacing between the valves. The dimensionless pressure drop, the mass flowrate coefficient, and the aerodynamic torque coefficient of each valve are used to characterize the system performance. The results show that the operating characteristics are strongly tied to the combined effect of the two valve disk angles. With noted exceptions, the valve disk orientation and spacing are secondary influences.

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Aerodynamic Torque Acting on a Butterfly Valve. Comparison and Choice of a Torque Coefficient

Journal of Fluids Engineering ◽

10.1115/1.2823555 ◽

1999 ◽

Vol 121 (4) ◽

pp. 914-917 ◽

Cited By ~ 9

Author(s):

C. Solliec ◽

F. Danbon

Keyword(s):

Pressure Drop ◽

Static Pressure ◽

Fluid Dynamic ◽

Dynamic Pressure ◽

Low Cost ◽

Normalization Method ◽

Pressure Drops ◽

Torque Coefficient ◽

Aerodynamic Torque ◽

Valve Pressure

Most technological devices use butterfly valves to check the flow rate and speed, through piping. Their main advantages are their low cost, their mechanical suitability for fast operation, and their small pressure drops when they are fully open. The fluid dynamic torque about the axis of large valves has to be considered as the actuator could be overstrained. This torque is generally defined using a nondimensional coefficient KT, in which the static pressure drop created by the valve is used for normalization. When the valve is closed downstream of an elbow, the valve pressure drop is not well defined. Thus, the classic normalization method gives many ambiguities. To avoid the use of the pressure drop, we define another torque coefficient CT in which the dynamic pressure of the flow is the normalization factor instead of the pressure drop. Advantages and drawbacks of each normalization method are described in the following.

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Assessments of Different Turbulence Models in Predicting the Performance of a Butterfly Valve

Volume 8: Computational Fluid Dynamics (CFD); Nuclear Education and Public Acceptance ◽

10.1115/icone26-82376 ◽

2018 ◽

Author(s):

Yu Duan ◽

Matthew D. Eaton ◽

Michael J. Bluck ◽

Christopher Jackson

Keyword(s):

Eddy Viscosity ◽

Turbulence Models ◽

Flow Coefficient ◽

Butterfly Valve ◽

Physical Measurements ◽

Viscosity Models ◽

Robust Model ◽

Sst Model ◽

Turbulence Effect ◽

Torque Coefficient

This paper presents an assessment of the performance of four eddy viscosity models in STAR-CCM+ 12.04 in simulating water flow through an industrial size butterfly valve: the standard k-ε model, realizable model, lag EB k-ε model and k-ω-SST model. This is achieved by comparing RANS predictions with physical measurements already available in literature. Although the lag EB k-ε model and k-ω-SST model are supposed to have a better ability to capture the anisotropic turbulence effect and flow separations, it has been demonstrated that the standard k-ε model is still a robust model in terms of predicting the flow coefficient (Cv). The general error of Cv by the standard k-ε model is less than 10% for the considered openings with the exception of 80°. This work also demonstrates that the eddy viscosity models have more difficulty predicting the torque coefficient (Ct) than Cv.

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Experimental and Numerical Analysis of Multi-Hole Orifice Flow Meter: Investigation of the Relationship between Pressure Drop and Mass Flow Rate

Sensors ◽

10.3390/s20247281 ◽

2020 ◽

Vol 20 (24) ◽

pp. 7281

Author(s):

Adam Tomaszewski ◽

Tomasz Przybylinski ◽

Marcin Lackowski

Keyword(s):

Numerical Analysis ◽

Pressure Drop ◽

Mass Flow ◽

Flow Coefficient ◽

Flow Meter ◽

Contraction Coefficient ◽

Single Hole ◽

Wide Range ◽

Orifice Flow ◽

Orifice Flow Meter

The paper presents the results of the experimental and numerical analysis of a six-hole orifice flow meter. The experiments were performed on humid air in a 100 mm diameter duct. The aim of this research was to investigate the mass flow and pressure drop dependency in an orifice of a predetermined shape and to compare the results obtained with computational formulas recommended in the ISO 5167-2 standard for a single-hole orifice flow meter. The experiments and calculations were performed on several multi-hole orifice geometries with different contraction coefficient in a wide range of Reynolds numbers. The pressure was probed immediately upstream and downstream of the orifice. The flow coefficient determined for the six-hole orifice flow meter investigated was compared with the flow coefficient of conventional single-hole orifice with the same contraction coefficient. The results from computational formulas for single-hole orifice from ISO 5167 are also included in the paper. During some experiments, an obstacle has been introduced in the duct at variable distance upstream from the orifice. The effect of the thus generated velocity field disturbance on the measured pressure drop was then investigated. Numerical simulation of the flow with the presence of the obstacle was also performed and compared with experimental data.

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