English  |  正體中文  |  简体中文  |  Items with full text/Total items : 63190/95884 (66%)
Visitors : 4590094      Online Users : 281
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version
    Please use this identifier to cite or link to this item: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/62575

    Title: 側向開口端部封閉管道中紊流器流場效應探討
    Other Titles: Turbulator effects on flow characteristics in side-open end-sealed duct flow
    Authors: 陳增源;郭哲翔
    Contributors: 淡江大學航空太空工程學系
    Keywords: 側向開口端部封閉管流;紊流產生器;Side-open end-sealed duct flow;Turbulator
    Date: 2006-03
    Issue Date: 2011-10-18 21:54:35 (UTC+8)
    Publisher: 臺北縣淡水鎮:淡江大學
    Abstract: 本研究利用側向閉口端部封閉管道, 實驗探討三角翼紊流產生器之流場效應。研究內容主要色括探討流體側向溢流以及紊流產生器對流場結構及邊界層內流場對流、二次流及紊流特性影響。一風洞系統用來產生空氣
    流於兩側閉口端部封閉管道入口,紊j炭產生器置於管道入口,流場雷諾數為1500 及15000 。實驗內容主要為管道斷函、邊界層內三維向穩態及非穩態速度量測。研究結果顯示,管道中央斷面流場有一般銜擊流特性;而靠
    近管道壁面之流鐘,受到底板所造成逆向壓力及壁面摩擦力雙重影響,導致逆向流產生;雷諾數小,軸向動能較小,因此雷諾數的00 時,其逆向it較雷諾數15000 提早發生。紊流產生器之影響,造成更大區域之逆向流以
    及較大區域之""死水區"" ,因而有較差之流場對流效應,但紊流產生器對近壁面流場效應,則可增加流場之二次流速度及紊流動能,有較佳之二次流效應及紊流效應。
    The study experimentally investigates the turbulator effects on flow characteristics in a side-open, end-sealed duct, which simulates the cooling passages in the fin-type heat sinks of electronic equipments. Specifically, this research investigates the effects of fluid side-leakage and turbulator on the flow structures and near-wall flow characteristics, such as the convective mean velocity, the secondary flow and the turbulent kinetic energy. A windtunnel system is used to generate a unifonn flow at the inlet of the side-open, end-sealed duct. A delta-wing turbulator is placed at the inlet of the duct for the turbulator-effect study. The Reynolds numbers are 1500 and 15000. The measurements include three-component mean and fluctuating velocities at duct cross-sections and near the duct wall. Results of this study indicate that the flow in the central plane of the duct is similar to an impinging flow. Due to the reverse pressure by the end wall and the friction force by the duct wall, the flow reversal occurs near the duct wall. The reversal flow occurs earlier for smaller Reynolds number than that for larger Reynolds because of the smaller flow kinetic energy. The effects of the turbulator causes lager dead water flow region and, thus, results in worse convective effect. However, the turbulator causes the larger secondary velocity and turbulent kinetic energy and, thus, results in better secondary and turbulent effects on the near-wall flow characteristics.
    Relation: 第五屆海峽兩岸航空太空學術研討會論文集,頁195-202
    Appears in Collections:[Graduate Institute & Department of Aerospace Engineering] Proceeding

    Files in This Item:

    File SizeFormat

    All items in 機構典藏 are protected by copyright, with all rights reserved.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - Feedback