ノズル内の二次元物体によって励起された二次元噴流の過渡特性 :(非調和的な励起条件における低周波数速度変動)

概要

論文の詳細を見る
Transitional characteristics of a plane jet excited by wake of a two-dimensional cylinder installed in nozzle contraction has been investigated by FFT and phase-averaging techniques. The slot width h of the nozzle was fixed to 15mm. The diameter of the cylinder d was 2mm, and the location of the cylinder inside the nozzle contraction X_c was 90 mm from the nozzle exit. The exit velocity was 10.1m/s, and Reynolds number based on the slot width was 1.0×10^4. In this setup condition of the cylinder, two distinctive spectral peaks (f_1 and f_2) centered at 1/2 the excitation frequency were observed. And also inharmonic phenomenon indicated by presence of beat frequency of the two frequencies was observed. The results show that the jet under inharmonic excitation exhibits flapping motion at frequency f_1-f_2, and the jet starts to rolling-up to form vortex street at x/h>8.
一般社団法人日本機械学会の論文
2000-09-25