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

基于2DVD的非旋轉(zhuǎn)折射式噴頭水滴直徑分布規(guī)律
作者:
作者單位:

作者簡介:

通訊作者:

中圖分類號:

基金項(xiàng)目:

國家工程技術(shù)研究中心再建項(xiàng)目(2011FU125Z27-1)、西北農(nóng)林科技大學(xué)科技創(chuàng)新專項(xiàng)資助項(xiàng)目(Z109021207)和教育部、國家外國專家局“111”計(jì)劃資助項(xiàng)目(B12007)


Drop Size Distribution of Fixed Spray-plate Sprinklers with Two-dimensional Video Disdrometer
Author:
Affiliation:

Fund Project:

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

    采用基于三維視頻粒子測量原理的視頻雨滴譜儀(Two-dimensional video disdrometer,2DVD)對噴灌機(jī)中常用的Nelson D3000型噴頭在多個(gè)工作壓力下水滴直徑沿射程的分布進(jìn)行了測量,分析了水滴直徑沿射程的變化趨勢及水滴速度、水滴角度與水滴直徑之間的關(guān)系。結(jié)果表明:水滴直徑與射程符合指數(shù)函數(shù)關(guān)系,在距離噴頭相同測點(diǎn)處,水滴直徑隨工作壓力的升高而減小,而射程末端的水滴直徑隨著壓力的升高而增大;水滴速度隨水滴直徑增加而增大,兩者呈對數(shù)關(guān)系;水滴落地時(shí)與地面夾角(簡稱水滴角度)隨水滴直徑增加呈減小趨勢,水滴直徑小于1.0mm時(shí),50、100、150和200kPa工作壓力下,與地面夾角為90°的水滴個(gè)數(shù)占總水滴數(shù)的比值分別為90.46%、84.46%、89.91%和89.15%,其余水滴與地面夾角在30°~89°之間,水滴直徑在1.0~2.25mm范圍內(nèi),水滴角度隨水滴直徑的增加迅速減小,水滴直徑大于2.25mm時(shí)減小趨勢變緩,4個(gè)工作壓力下最大直徑水滴落地時(shí)與地面夾角平均值為45°;工作壓力對于水滴直徑與速度、水滴直徑與角度之間的關(guān)系影響較小。

    Abstract:

    A two-dimensional video disdrometer (2DVD) was used to measure drop size, drop velocity and drop angle from Nelson D3000 spray-plate sprinklers with a 4.78mm nozzle and operating pressure of 50, 100,150, 200kPa. The relationship among drop sizes, drop velocity and drop angle were analyzed. Results indicated that the relationship between drop diameter and distances along the sprinkler met exponential function. The volumetric mean diameter increased with the distance along the sprinkler increased, and at the same location from the sprinkler the average droplet diameter decreased with the increase of working pressure. The relationship between drop velocity and drop diameter met logarithmic function. Drop velocity increased with the drop diameter increased, and the effect of operating pressure on the relationship between drop diameter and velocity was not obvious. Drop angle decreased with the increase of drop diameter. When drop diameter was smaller than 1.0mm and operating pressure was at 50, 100, 150, 200kPa, 90.46%, 84.46%, 89.91% and 89.15% of the droplets descended perpendicularly to the ground, respectively. The rest of the droplets descended to the ground with angle between 30°~89°. When drop diameter was between 1.0mm and 2.25mm, the drop angle decreased rapidly with the drop diameter increased. And when drop diameter was greater than 2.25mm, the decrease trend became slower. The relationship between drop angle and drop diameter met a good linear function, and the effect of operating pressure on the relationship between drop angle and diameter was not obvious.

    參考文獻(xiàn)
    相似文獻(xiàn)
    引證文獻(xiàn)
引用本文

鞏興暉,朱德蘭,張林,張以升,葛茂生,楊雯.基于2DVD的非旋轉(zhuǎn)折射式噴頭水滴直徑分布規(guī)律[J].農(nóng)業(yè)機(jī)械學(xué)報(bào),2014,45(8):128-133,148. Gong Xinghui, Zhu Delan, Zhang Lin, Zhang Yisheng, Ge Maosheng, Yang Wen. Drop Size Distribution of Fixed Spray-plate Sprinklers with Two-dimensional Video Disdrometer[J]. Transactions of the Chinese Society for Agricultural Machinery,2014,45(8):128-133,148.

復(fù)制
分享
文章指標(biāo)
  • 點(diǎn)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:2014-01-20
  • 最后修改日期:
  • 錄用日期:
  • 在線發(fā)布日期: 2014-08-10
  • 出版日期: