Abstract
Aiming at the internal leakage problem of spring type nuclear safety valve at the sealing surface, the flow field and sound field characteristics at the leakage height of 0.5mm between the valve disc and the valve seat sealing surface were studied, and the numerical simulation was carried out based on large eddy simulation(LES) and mohring acoustic analogy method, and compare the effects of acoustic wall pressure fluctuation(AWPF) and turbulent wall pressure fluctuation(TWPF) as the excitation source on the external sound field of the valve. The simulation results show that: the change gradient of velocity field and pressure field at the leakage port of safety valve is significant and form vortices of different sizes. The small-scale vortices are mainly in the leakage port, while the large-scale vortices mainly exist in the flow channel; When the valve is leaking, the noise is mainly dominated by high-pressure injection noise, its spectrum curve shows wide-band characteristics, and the external noise of the valve is mainly caused by AW P F. The above research results can provide a theoretical basis for the safety valve online detection method.
Highlights
IntroductionThe safety valve is widely used in various fields. As an overpressure protection device, internal leakage is the main failure mode
Nowadays, the safety valve is widely used in various fields
The flow field of safety valve is calculated by Fluent
Summary
The safety valve is widely used in various fields. As an overpressure protection device, internal leakage is the main failure mode. There are more and more technologies for valve leakage detection at home and abroad, such as acoustic emission testing, vibration analysis and ultrasonic testing methods ,etc[2,3].The paper[4,5] used CFD and acoustic software to study the flow field and aerodynamic noise problems during valve internal leakage, and verified the feasibility of this method. Based on the LES and mohring acoustic analogy, the variation of velocity field and pressure field as well as the frequency spectrum characteristics of internal and external noise of the valve are analyzed, which provides a certain data basis for establishing the relationship between noise and leakage, and for the leakage acoustics inside the safety valve Online monitoring provides a theoretical basis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
