Self-Induced Vibration Caused by Spray Valve in Deaerators

• Published in: Transactions of the Japan Society of Mechanical Engineers Series C Vol. 53; no. 487; pp. 696 - 702
• Main Authors: FUNAKAWA, Masaya, ISHIMATSU, Takakazu
• Format: Journal Article
• Language: English; Japanese
• Published: The Japan Society of Mechanical Engineers 1987
• Subjects: Deaerator; Flow-Induced Vibration; Self-Induced Vibration; Spray Valve; Two Degrees of Freedom
• ISSN: 0387-5024; 1884-8354
• DOI: 10.1299/kikaic.53.696

In a deaerator, which is used for the treatment of feed water of boilers, there have been rarely induced severe vibrations in the shell and spray valve. It has been considered that the vibration is self-induced by coupling between valves and shells. However the detail of the excitation mechanism of the vibration is not yet clear. In this study, the vibration of the value and the tank wall, pressure in the tank and the flow rate from the valve are measured experiementally through various contractions of the coil spring of the valve and thickness of the tank wall. By these experimental results, it has been concluded that the self exciting mechanism of the vibration is the pressure variation in the tank caused by vibrations of the spray valve and tank wall. Furthermore by the computation of the stability of this system, it is concluded that additional damping in the valve is very effective for the suppression of the vibration.