Experimental and numerical investigations of choked air flow and heat transfer in a ball valve for optimization the cross-sectional area

Abstract

Purpose

The purpose of this study is to understand the functional properties of ball valve in a compressible flow and simulation of experimental data collection of ball valve, was completely simulated.

Design/methodology/approach

Equations are solved according to finite volume and simplified algorithms. By measuring the flow parameters, including pressure and temperature at different points in the simulation circuit, flow coefficients and localized drop in the valve were determined in different openness cases of test valve and compared with experimental results. Determining a graph for flow coefficient variations in terms of the percentage of openness of the valve is very effective on the flow control as well as on optimizing its cross-section.

Findings

In the supersonic flow, flow coefficients and local drops of the valve are dependent on several parameters, including fluid flow rate. Flow coefficient graphs at different angles of the test valve show that by increasing the valve opening angle, the flow coefficient increases so that it reaches from 1.72 m³/h at a 30° angle to 46.29 m³/h at a 80° angle. It should be noted that these values in the experimental test were obtained 1.53 m³/h and 49.68 m³/h, respectively, and the percentage difference of these values by simulation was obtained for the angle of 30 degrees 11.7% and for the angle of 80°, about 7% per hour at an angle of 80°. Also, the coefficients of localized loss at different angles of test valve show that by increasing the angle of opening of the valve, the amount of localized loss decreases, so that the average value of 1515.2 in the angle of 30° reaches 1.9 at an angle of 80°. The percentage difference of these values by simulation, for the angle of 30° and 3.5% for the angle of 80°, was about 11.1%.

Originality/value

Determining a graph for flow coefficient variations versus the percentage of openness of the valve is very effective on the flow control as well as on optimizing its cross-section. In the supersonic flow, flow coefficients and local drop coefficients of the valve are dependent on several parameters, including fluid flow rate.

Citation

Toghraie, D. and Khouzani, H.H. (2020), "Experimental and numerical investigations of choked air flow and heat transfer in a ball valve for optimization the cross-sectional area", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 30 No. 5, pp. 2705-2737. https://doi.org/10.1108/HFF-05-2019-0398