本文係在均勻紊流場中,以紊流強度及紊 流尺度為紊流參數,探討其對二維方柱體風力 係數、風力頻譜及風力空間相關性之影響。而 由實驗結果顯示,紊流強度強烈地影響分離剪 力層之渦漩形成發展,及減弱模型側面之渦散 作用,使得橫風向之空間相關性因而降低。而 平均阻力係數(C/sub d/)及擾動性昇力係數 (C/sub l/')亦因此下降。對於二維方柱體之風力 係數及風力頻譜影響,主要為導因於紊流強度 之變化,且遠大於紊流尺度效應之影響。 Experimental studies were conducted to investigate aerodynamics of 2-D square cylinder in turbulent flows. The two dimensional turbulent flows were generated by properly controlling the turbulence intensity and length scale. The mean and r.m.s. force coefficients, pressure coefficients, power spectral densities, correlation length scales were studied during this research program. Results indicate that turbulence intensity cast strong effects on, force coefficient (C/sub d/, C/sub l/'), correlation length, and the separation-reattachment phenomenon, while turbulence length scale show will effect on C/sub d/' and C/sub p/'.
中華民國力學學會第十六屆全國力學會議論文集(一)=Proceedings of the 16th National Conference on Theoretical and Applied M=echanics (I)