Study on the influence of Volute to Flow-induced Noise in Centrifugal Pump

摘要

More and more attention has been attached on flow-induced noise of centrifugal pump in recent years because of strict environmental noise restrictions and demands of clients.. In this paper, the role of volute impacted on flow-induced noise generation and propagation in centrifugal pump were summarized. The process of internal wave propagation was analyzed, and the transmission coefficient and loss of volute were calculated; In order to compare the effect of volute vibration on the sound field in a centrifugal pump, a hybrid algorithm based on CFD + BEM was adopted. The results reveals that: full reflection of sound wave occurs on the fluid-steel volute wall when the incidence angle is more than or equal to 13.8 °; otherwise a sound transmission appears; For onshore pumps, For onshore pumps the A-weighted sound transmission loss is more than 55dB under the condition that thickness volute is not less than 8mm; For submersible pumps, all-bottom sound below 3000Hz almost transmits to the outside field entirely; structure acoustic coupling between volute and the internal sound field influence little on directivity of sound field and the change of law, but structure vibration would average the sound pressure level in frequency.