Valve noise prediction and acoustic scale modeling

Abstract

The noise from industrial piping systems containing control valves and regulators with compressible fluids is the result of four processes each of which are rather complicated. First, noise generation at the valve orificial element. Second, development of the acoustic field in the downstream pipe. Third, the interaction of the modes of the acoustic field with the like pipe vibratory modes; and fourth, the radiation from vibrating pipe wall surface into the surroundings. Recent research has shown that noise generation formulation based on the free, choked jet, shock-turbulence interaction gives results in good agreement with test. Also, most of the radiated energy is emitted at the coincidence frequencies of the downstream piping. The paper discusses the scaling implications of these relationships with regard to valve size, valve pressure drop, and fluids. Some of the difficulties of applying scaling laws in view of lack of geometric similarities in valve families prevelant in past work is considered.