1002 後流平板によるカルマン渦励振の振幅増大のメカニズム(OS10-1 流体関連振動・騒音,オーガナイズドセッション)
詳細
A crisscross arrangement downstream strip plate enhances Karman vortex induced vibration of a circular cylinder and a square cylinder under certain conditions (EKVIV). Wind tunnel experiments were carried out to investigate influence of the strip plate width w and length l_d on EKVIV. When w/d < 0.5 and l_d was enough long compared with the cylinder characteristic length d, KVIV of the circular and the square cylinder was enhanced, while wider plates can suppress KVIV. In addition, EKVIV occurs on the square cylinder when l_d/d ≤ 6 though w is broad that is w = d. Spectrum peak values (S_u)_<peak> and spanwise cross correlation R_<12> of velocity fluctuation, which corresponds to Karman vortex shedding, were measured to reveal change in wake flow. When w/d < 0.5, (S_u)_<peak> increases in range of 0.4 ≤ s/d ≤ 1.4. When w/d = 0.5 and 0.8 ≤ s/d ≤ 1.4, R_<12> increases all over spanwise except the cylinder and the plate crossing.
