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.