Causes and Countermeasures of Abnormal Tones of Once-Through Boiler

Kunihiko Ishihara

Aerodynamic acoustics, Once-through boiler, Resonance, Self-sustained tone, Plate with holes

This paper describes the causes of abnormal tones generated from the small boiler and the countermeasures to suppress it. The abnormal tones caused by the acoustic resonance or the self-excited mechanism have ever been experienced. The baffle plate has been well used to suppress such kinds of tones. This countermeasure, however, can’t be applied to the present boiler (called once- through boiler) because of the flow directional resonant mode. Then, the wall with holes was used to weaken the vortex strength which caused the abnormal tones. As a result, the abnormal tones disappeared completely.

https://dx.doi.org/10.31873/IJEAS.8.6.04