查詢結果分析
來源資料
相關文獻
- The Effects of Turbulence on Mean Flow Past Fixed and Oscillating Rectangular Prisms
- Aerodynamics of a Vibrating Square Prism in Homogeneous Turbulent Flows
- 紊流強度與尺度及矩柱斷面對渦散的影響
- Aerodynamic Forces on Two Stationary and Oscillating Square Prisms in Tandem and Side by Side Arrangements
- 直升機風洞測試模型之機電硬體設計與製作
- 都市地區建築物風環境及風壓之風洞模擬試驗研究
- Vortex Shedding from Fixed and Oscillating Rectangular Prisms in Shear Flows
- 橫風向振動對三維方柱體所受風力特性的影響
- 直提式閘門振動分析評估之研究
- 方柱體於剪力流場中之流場特性研究
頁籤選單縮合
題名 | The Effects of Turbulence on Mean Flow Past Fixed and Oscillating Rectangular Prisms=紊流場中振動矩柱之尾跡現象研究 |
---|---|
作者姓名(中文) | 盧博堅; 鄭啟明; 高忠人; | 書刊名 | 中國工程學刊 |
卷期 | 20:6 1997.11[民86.11] |
頁次 | 頁615-622 |
分類號 | 440.137 |
關鍵詞 | 強制振動; 渦散; 均勻紊流; 風洞測試; Forced oscillating; Vortex shedding; Uniform turbulent flow; Wind tunnel testing; |
語文 | 英文(English) |
中文摘要 | 本文探討二維矩柱靜止及振動下於均勻紊流場中之渦期(vortex shedding)變化情形。控 制參數為矩柱的深寬比;逼近流場的紊流強度與紊流尺度;振動頻率及固定振幅。量測項目為模型 軸中間側面及背面中點之單點壓力,尾跡中單點速度量測,及側面壓力和柱體位移之相位差。 實驗結果顯示,振動矩柱之平均側面壓力係數(-c□)、背面壓力係數(-c□)、擾動性側壓係 數(c□),背壓係數(c□)、及壓力頻譜和速度頻譜之尖峰值於鎖定範圍內皆會升高,尤其在共振 點達到最高。紊流強度的增加,會增加剪力層混合,因而減弱渦散作用,使得壓力係數下降,頻譜 尖峰值下降且變為寬頻。臨界深寬比為0.6,增加紊流強度會造成臨界深寬比的減小。 |
英文摘要 | The characteristics of vortex wakes of rectangular prisms, with and without forced oscillation, were experimentally investigated, as placed in different uniform turbulent flows. The experimental param- eters were the turbulence intensities and length scales of the uniform turbulent flows and the depth-to-width ratios and vibrating frequencies, with fixed amplitudes, of the rectangular prisms. Measurements were taken on the lateral pressure and base pressure of the prisms, the point velocity in the wake, and the phase angle between lateral pressure and body displacement. The pressure coefficients(-c□, -c□, c□, c□)are much greater when the oscillating cylinder is in lock- in range and reach peak values at resonant frequencies in a uniform flow. High turbulence intensity weakens the vortex shedding, thereby decreasing the pressure coefficients and peak values of the spectra. Increasing the turbulent length scale causes the pressure coefficients to increase. The critical depth-to-width ratio is found at H/D=0.6, while decreasing in this ratio results owing to increases in turbulence intensities. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。