0617 ボイラにおける気柱共鳴現象の発生に及ぼす管群配列の影響(OS6 流体関連振動・騒音,オーガナイズドセッション)

Abstract

In the present paper the attention is focused on effect of arrangement of tube banks on acoustic resonance which occurred in the two-dimensional model of boiler.We have examined the characteristics of vortex shedding and acoustic resonance generated from in-line and staggered tube banks.At the small tube pitch ratio in in-line tube banks,acoustic resonance of third mode and fourth mode occurred.The alternative vortex shed from in-line tube banks and its frequency became broad-band.On the other hand,at the small tube pitch ratio in staggered tube banks,acoustic resonance did not occurred,although the vortex shed at the resonance frequency in the tube banks.The pressure drop at staggered tube banks was larger than that of in-line tube banks.The symmetric vortices were observed inside staggered tube banks at the small tube pitch ratio.