基于非定常湍流分析的流程阀门启闭过程动态特性研究

流程阀门是广泛应用于石油、化工等流程工业的管道流体控制元件。阀门的启闭动态特性直接影响流程阀门的可靠运行。因此需从流程阀门启闭过程内部流动的动态特性着手，建立不同启闭规律下阀门过流断面上下游内部流动参数与外特性的关联规律,目前针对启闭过程的瞬态流动研究开展得较少。启闭过程中阀门内的流动属于有压驱动的变断面非定常流动。本项目拟通过理论分析、数值模拟和阀内外特性的实验研究，分析小开度时壁面对过流断面流动的影响来修正湍流模型，建立适合阀门启闭瞬态流动过程的数学模型；在不同启闭规律下，研究变过流断面对内部流动的影响机理，分析过流断面变化规律与过流断面上下游内部流动特性的映射关系，揭示阀门内部瞬态流动机理，提出启闭过程中阀门外特性与内部流场的关联规律，为提高流程阀门的动态性能和在启闭过程中的运行可靠提供理论支撑。

Process valve as pipe flow control components is widely used in petroleum, chemical industries. The opening-closing dynamic characteristic has the direct influence on the operation reliability, so the dynamic characteristic of the internal flow in valve should be investigated to establish the association law between flow parameters of upstream and downstream and external characteristic. At present, few researches on the transition flow of opening-closing process are carried. The flow in valve in the process of opening and closing is pressure-drive variable-section unsteady flow. In this project, the method of theoretical analysis, numerical simulation and experimental study on process valve are applied to investigate the influence of the wall on the cross-section flow to modify the turbulence model under the condition of small opening. The mathematical model will be established appropriate for transition flow in the process of opening and closing of valve. The influence of variable cross section on the internal flow is studied at different opening and closing law. The mapping relationship between the variable laws of cross section and internal flow characteristic of its upstream and downstream is analyzed. The transition flow mechanism of valve will be revealed. The association law between external characteristic and internal flow will be presented in the process of opening and closing. This will provide the theoretical support for improving the dynamic performance and operation reliability in the process of opening and closing.