密な円管群を過ぎる流れ : 第2報,流れ方向の配列を変化させた場合の管群内流れの速度変動と線形振動解析

概要

論文の詳細を見る
Vibration and acoustic resonance of tube banks of a boiler heat exchanger are some of the most important problem. The main causes of these problems is induced cross flow through the tube banks that gives rise to fluctuation at some frequency. However, there is no report that explained velocity fluctuations in closely arranged circular cylinders. This present paper is concerned with the excitation mechanism of velocity fluctuation in closely arranged staggered tube banks. We measured the frequency of velocity fluctuation for nine arrays in the range of Re_s=1.0×10^4 to 9.4×10^4. In these results, Strouhal numbers tend to increase as longitudinal spacing ratio decrease and we measured several Strouhal numbers at the tube arrangement with X_T=2.O, X_L=1.4 and X_T=2.O, X_L=1.8. Analysis of the frequency was done by the use of a linear instability model in which instability occurs due to the unbalance between friction and pressure difference. The result of this calculation agrees quite well with available experimental data.
一般社団法人日本機械学会の論文
1996-04-25