ACOUSTIC NOISE REDUCTION IN LARGE-DIAMETER STEAM-LINE GATE VALVES

摘要

High levels of tonal noise continue to be a potential problem for piping systems that include inline gate valves, particularly for valves located in large-diameter steam lines of power plants. In such cases the large amounts of energy available in the flowstream, and the ineffectiveness of design guidelines in avoiding acoustic excitation, combine to provide a very real possibility of severe noise problems and potentially high levels of piping vibration. This paper presents results of a scale-model testing program designed to investigate the excessive noise and vibration produced by a 28"-diameter gate valve in a recently constructed power plant. After model testing of the original valve configuration indicated that the noise was caused by vortex shedding over the valve's interior cavity, numerous tests were conducted to investigate the dependence of noise production on interior valve geometry. Results showing how the noise was reduced and recommendations for avoiding such problems are presented.