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低壓灌溉管道輸渾水阻力損失試驗與建模
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國家自然科學基金資助項目(50909062、51269028)和石河子大學自然科學基金資助項目(ZRKX2010YB15)


Experiment and Modelling on Resistance Loss of Muddy Water Delivery for Irrigation in Low-pressure Pipeline System
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    摘要:

    通過低壓管道輸水阻力損失試驗,分別研究了清水和渾水條件下的阻力損失變化規(guī)律。清水條件下,得到了清水阻力系數(shù)與清水雷諾數(shù)的定量關系式,可以用于后續(xù)清水阻力損失的計算;渾水條件下,重點分析了渾水阻力損失隨流速和含沙量體積比的變化規(guī)律,其中渾水阻力損失隨流速的增大而增大,在含沙量較小時,隨含沙量體積比增大而增大,在含沙量較大時卻隨含沙量體積比增大而減小,并從泥沙的制紊和減阻角度分析了產生這種變化規(guī)律的原因。研究了渾水阻力損失系數(shù)變化規(guī)律,得到了阻力損失系數(shù)與無量綱綜合因子之間定量關系式,試驗結果與標準Durand和陳廣文計算模型驗證比較表明:兩種模型計算結果與試驗結果存在較大差異,不能用于計算管道渾水阻力損失。根據(jù)試驗結果得到了渾水阻力損失與水流弗勞德數(shù)和含沙量體積比乘積以及泥沙沉降弗勞德數(shù)之間定量關系式,該關系式相關系數(shù)R=0.90,擬合度較高,可以用于實際工程渾水阻力損失計算。

    Abstract:

    Through experimental study on resistance loss of water delivery in pipeline system, the variation laws of resistance loss for clean and muddy water were researched respectively. In clean water experiment, the quantitative formula between resistance loss coefficient of clean water and Reynolds number was achieved. It could be used to calculate resistance loss of clean water. In muddy water experiment, the variation law of resistance loss with the difference of velocity and sediment content was focused on, which the resistance loss increased with the increasing of velocity. On the condition of small sediment content the resistance loss increased with the increasing of sediment content, while it decreased with the increasing of sediment content on the condition of large sediment content. The reason for producing this variation law of resistance loss was analyzed from turbulence prevention and drag reduction by sediment. Based on this analysis, the variation law of resistance loss coefficient for muddy water was researched, and the calculation formula between the resistance loss coefficient and the dimensionless comprehensive factor was developed. Comparison between the experimental results and standard Durand and Chen Guangwen calculation model showed that there was large difference between them, and the existing models couldnt applied to calculate the resistance loss of muddy water. According to the results of experiment, the quantitative formula, between resistance loss and the product of the flow Froude number and sediment concentration, and the Froude number of sediment deposition was developed. Result showed that the correlation coefficient R was 0.90. 

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宗全利,湯驊,安杰.低壓灌溉管道輸渾水阻力損失試驗與建模[J].農業(yè)機械學報,2013,44(6):148-155. Zong Quanli, Tang Hua, An Jie. Experiment and Modelling on Resistance Loss of Muddy Water Delivery for Irrigation in Low-pressure Pipeline System[J]. Transactions of the Chinese Society for Agricultural Machinery,2013,44(6):148-155.

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  • 在線發(fā)布日期: 2013-05-28
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