Flow characteristics analysis of novel dual-sleeve control valves with multi-shape throttling windows

Abstract

Sleeve control valves are widely used for accurate flow modulation in industrial processes. However, traditional sleeve control valves usually rely only on axial adjustment, with fixed flow characteristics predefined during the manufacturing stage, which limits regulation accuracy and adaptability under diverse operating conditions. In this paper, a novel dual-sleeve control valve with two degrees of freedom in both axial and circumferential directions is designed. In this design, the flow coefficient is a two-dimensional function of the opening degrees, extending the traditional flow characteristic curve into a three-dimensional surface. The dual-axis-adjusted flow characteristics surface is accurately fitted by a quartic polynomial function. Next, the effects of three representative throttle window geometries - rectangular, triangular and funnel-shaped - on flow characteristics are investigated. Multiple inherent flow characteristics including the partial derivatives and gradient of flow coefficients are analyzed and evaluated to reveal regulation sensitivity. Furthermore, a prediction model is proposed to map flow characteristic surfaces to shape factors, allowing designers to obtain valve performance directly without repeated simulations or experiments. Finally, an automatic opening selection method is developed, balancing accuracy and response time. This work is valuable for the design and accurate regulation of sleeve control valves, enabling them to meet a wider range of operational conditions in practical engineering applications.