Numetrical Simulation And Optimization Analysis Of Interior Flow Field Within A Pressure Regulating Valve

With the development of oil refining industry and technology, product oil pipelines system mainly composed of trunk pipelines has been formed basically. When oil is needed in local regions, the trunk pipelines connecting with the advanced assembly pipelines can meet the temporary requirements. Due to the long-distance transportation, the fluid pressure in product oil pipelines is generally more than 10MPa. However, the internal pressure of assembly oil pipelines with lightweight design for high efficient transportation and installation is generally less than 6MPa. The pressure regulating valves should be used as a pressure conversion device to ensure the safety of the temporary oil supply system. Therefore, it’s particularly important to study the internal flow field distribution and ensure the safety of the pressure regulating valve in docking condition.This dissertation focuses on a pressure regulating valve which is used in docking condition and mainly does the following works:1. Based on the docking condition and the theoretical knowledge of valves, the structure features, working principle and related characteristics of the pressure regulating valve are present2. By simulating interior flow field of the initial pressure regulating valve, the distributions of velocity, pressure and streamlines in docking condition are obtained. The theoretical flow characteristic curve is got by analysis. According to the simulation results and the working requirements, the working reliability of the initial design pressure regulating valve is ensured. The results indicate that the initial design pressure regulating valve can be reliably used in docking condition.3. By simulating interior flow field of the improved pressure regulating valve, the graphical visualizations and the theoretical flow characteristic curve in docking condition are obtained. According to the simulation results and the working requirements, the working reliability of the improved pressure regulating valve is ensured. Meanwhile, the improved valve is tested in the laboratory bench. The comparison and analysis between experimental results and simulation results verify the reliability of the simulation method.4. The tooth-cascade structure is analyzed by comparing interior flow field and relevant parameters between initial and improved pressure regulating valve. The results show that the tooth-cascade structure has great effects on throttling and preventing cavitation.5. The shape of the second stage orifices of the improved pressure regulating valve are optimized due to the docking condition and the working reliability. The advantages of the optimized programs are obtained by comparing simulated results with prior optimization. This dissertation provides references for better use of the pressure regulating valve under docking condition.