亚洲一区欧美在线,日韩欧美视频免费观看,色戒的三场床戏分别是在几段,欧美日韩国产在线人成

滴頭鋸齒型迷宮流道消能特性的流體動力學分析
作者:
作者單位:

作者簡介:

通訊作者:

中圖分類號:

基金項目:


Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 圖/表
  • |
  • 訪問統(tǒng)計
  • |
  • 參考文獻
  • |
  • 相似文獻
  • |
  • 引證文獻
  • |
  • 資源附件
  • |
  • 文章評論
    摘要:

    在對所選取的3種代表性鋸齒型迷宮式滴頭流道參數(shù)進行精確測定的基礎上,利用圓管紊流理論和CFD流場模擬軟件對鋸齒形迷宮流道的消能機理進行了研究。結果表明:光滑圓管紊流理論不足以解釋鋸齒型迷宮流道的消能機理;壓力沿流道長度方向呈線性遞減,各消能尖角單元壓力損失相等,符合線性疊加規(guī)律;摩阻系數(shù)隨著壓力增加而降低,并很快穩(wěn)定在一定數(shù)值上;在中、高壓區(qū)滴頭流道內(nèi)部流動為紊流,在低壓區(qū)可能存在從層流到紊流或者光滑紊流到全紊流的流態(tài)轉捩行為。

    Abstract:

    Labyrinth path drip irrigation emitter is one of the predominant drippers. Based on the exact test to the geometry parameters of three representative sawtooth-labyrinth paths, the mechanism of pressure losses in the flow path was studied by the smooth pipe turbulence theory and CFD (computational fluid dynamics)technology of flow regime. The mechanism of pressure losses in sawtooth-labyrinth path couldn't be explained with smooth pipe turbulence theory. The pressure was descending with linearity rules along the flow path, and the head losses was equaled. The friction coefficient reduced with the pressure increasing, and it was stabilized to a value soon. The flow regime is turbulent within the sawtooth-labyrinth paths the pressure zone higher than 50 kPa, and it is possible that the transformation behaviors of the flow from laminar flow or smooth turbulent into turbulent flow were existed. 

    參考文獻
    相似文獻
    引證文獻
引用本文

李云開,劉世榮,楊培嶺,任樹梅,林雄財.滴頭鋸齒型迷宮流道消能特性的流體動力學分析[J].農(nóng)業(yè)機械學報,2007,38(12):49-52.[J]. Transactions of the Chinese Society for Agricultural Machinery,2007,38(12):49-52.

復制
分享
文章指標
  • 點擊次數(shù):
  • 下載次數(shù):
  • HTML閱讀次數(shù):
  • 引用次數(shù):
歷史
  • 收稿日期:
  • 最后修改日期:
  • 錄用日期:
  • 在線發(fā)布日期:
  • 出版日期: