New Cross-section Model for Full Bore Ball-valves

Abstract

The energy-efficient control of heating systems is a highly perspective issue. Retrofitting old heating systems require flow control valves which can provide linear control of flowrate; therefore, an accurate model is needed to be able to use simulation methods to efficiently optimize these systems. The Simscape toolbox of MATLAB/Simulink, widely used in engineering practice, includes a ball valve model that can be used as a throttle; however, the model may not be sufficiently accurate. In this research, a comprehensive mathematical model describing the flow cross-section of a ball valve is presented. An experimental system was built to be able to verify simulated data, thus validate the developed model. The developed and Simscape model is compared to measured data which shows a significant accuracy improvement. This study presents a new improved ball-valve model that considers the real geometry of the valve providing accurate simulation results, making it possible to simulate retrofitted systems with ball-valves.