頁籤選單縮合
題名 | Analysis of Flow and Heat Transfer on a Rough Rotating Disc=具粗造度自由轉盤熱流場分析 |
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作者姓名(中文) | 田華忠; 袁至杰; 雷顯宇; | 書刊名 | 中國機械工程學刊 |
卷期 | 20:3 1999.06[民88.06] |
頁次 | 頁257-266 |
分類號 | 446.0131 |
關鍵詞 | 粗糙度自由轉盤; 熱流場; Roughness; Forced Convection; Free Disk; |
語文 | 英文(English) |
中文摘要 | 本文對粗糙轉盤上的熱流場加以分析,並與平滑轉盤之結果相比較,以檢視粗糙 度的效應。對描述轉盤熱流場之邊界層動量及能量方程式以相似轉換處理,在層流區域,熱 流場均為相似,故形成一常微分方程組;至於紊流區則形成偏微分方程組。層流區以Runge- Kutta四階積分法並加以shooting方法求解,紊流區則採BoxMethod。研究結果顯示粗糙度 含減小轉盤表面的速度及溫度梯度,但對力矩係數及表面熱傳率有增進的作用。根據以往文 獻及本研究之結果與實驗結果的比較顯示粗糙轉盤上之流場其轉變雷諾數(R□)應有提前的 傾向。 |
英文摘要 | Flow and heat transfer on a rotating disc in a free space is analyzed in this study. The effects of surface roughness are investigated by comparing the results for a rough disc with that for a smooth disc. The boundary layer momentum and energy equations are transformed into a system of ordinary or partial differential equations, depending upon whether the flow is laminar or turbulent. In the laminar flow region, the fourth order Runge-Kutta integration method along with a shooting technique is employed, while in the turbulent flow region the Box Method is used. It is shown that an increase of the surface roughness will decrease the velocity and the temperature gradients at the disc surface. However, the moment coefficient and the heat transfer rate are enhanced by the increase of the roughness. A comparison between the present study and a previous investigation reveals that the transitional Reynolds number for a rough disc should he smaller than that for a smooth disc. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。