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仰角可調(diào)搖臂式噴頭水力性能試驗(yàn)
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“十二五”國(guó)家科技支撐計(jì)劃資助項(xiàng)目(2011BAD29B08)


Experiments on Hydraulic Performance of Impact Sprinkler with Adjustable Elevation Angle
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    摘要:

    在不改變噴頭原有結(jié)構(gòu)的基礎(chǔ)上,設(shè)計(jì)了一種由上支撐桿、下支撐桿、限位桿、柔性波紋管組件、內(nèi)螺紋空心軸、定位螺釘、調(diào)節(jié)螺釘?shù)冉M成的噴頭仰角調(diào)節(jié)機(jī)構(gòu),實(shí)現(xiàn)噴頭仰角在13°、18°、23°、30° 4個(gè)角度的調(diào)節(jié),并對(duì)安裝了該機(jī)構(gòu)的噴頭進(jìn)行了水力性能試驗(yàn)。結(jié)果表明, 噴頭仰角為23°時(shí),不同工作壓力下噴頭的射程均最大;在23°與30°時(shí)組合均勻度系數(shù)相對(duì)較大,最利于組合噴灌。不同工作壓力下,平均噴灌強(qiáng)度隨著噴頭仰角的減小而增大。噴頭仰角由23°減小到13°時(shí),噴頭噴灑水滴的飄移損失減小,平均噴灌強(qiáng)度增加,因此噴頭仰角減小可以增強(qiáng)其抗風(fēng)、抗坡能力。仰角越小,噴頭射程末端降水量變化越劇烈,導(dǎo)致噴頭噴灑降水量分布不均,所以仰角調(diào)節(jié)不宜過(guò)小。安裝了仰角調(diào)節(jié)機(jī)構(gòu)的噴頭在各象限的轉(zhuǎn)動(dòng)誤差均小于±10%,其轉(zhuǎn)動(dòng)均勻性符合要求。

    Abstract:

    To adjust the elevation angle of sprinkler and reduce the effect of wind on water distribution, a set of adjustment device which fixed on the original structure of the sprinkler was developed. The adjustment device consisted of support bar, limited rod, flexible metallic hose, internal thread hollow shaft sleeve, set screw and adjusting screw. Four elevation angles of sprinkler nozzle (13°, 18°, 23°and 30°) could be adjusted and fixed respectively. To evaluate the hydraulic performance of the sprinkler with adjustment device, a series of indoor experiments were conducted. The results showed that the characteristics of single sprinkler with adjustment device changed evidently at different elevation angles. When elevation angles of the sprinkler were 23° and 30°, the combinatorial uniformity coefficients were larger than that at 13° and 18°, so it was more practicable in combinatorial sprinkler irrigation. Under different working pressures of 0.20, 0.25 and 0.30MPa, the average sprinkler irrigation intensity increased with decrease of sprinkler elevation angle. Distribution of sprinkler water in the spraying end was more uniform at elevation angle of 23° than that at other angles in which the distribution of sprinkler water changed greatly and average sprinkler irrigation intensity increased accordingly. So decrease of elevation angle could reduce the effect of wind on water distribution effectively. On the other hand, because of the drastic variation of distribution of sprinkler water, the elevation angle of the sprinkler could not be too small. The rotation deviation of the adjustment device of sprinkler was less than ±10%. The test results indicated that it reached the indexes of JB/T 7867—1997.

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李星恕,張建賓,韓文霆.仰角可調(diào)搖臂式噴頭水力性能試驗(yàn)[J].農(nóng)業(yè)機(jī)械學(xué)報(bào),2015,46(2):34-39. Li Xingshu, Zhang Jianbin, Han Wenting. Experiments on Hydraulic Performance of Impact Sprinkler with Adjustable Elevation Angle[J]. Transactions of the Chinese Society for Agricultural Machinery,2015,46(2):34-39.

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  • 收稿日期:2014-04-03
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  • 在線發(fā)布日期: 2015-02-10
  • 出版日期: 2015-02-10
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