Numerical simulation of leakage flow field and acoustic characteristics for safety valve

Aiming at the internal leakage problem of spring type nuclear safety valve sealing surface, flow field and sound characteristics height 0.5mm between disc seat surface were studied, numerical simulation was carried out based on large eddy simulation(LES) mohring acoustic analogy method, compare effects wall pressure fluctuation(AWPF) turbulent fluctuation(TWPF) as excitation source external valve. The results show that: change gradient velocity port is significant form vortices different sizes. small-scale are mainly in port, while large-scale exist channel; When leaking, noise dominated by high-pressure injection noise, its spectrum curve shows wide-band characteristics, caused AW P F. above research can provide a theoretical basis for online detection method.