圆形出口全射流喷头盖板结构优化与喷洒均匀性试验

Spraying Uniformity and Cover Plate Structural Parameters of Circular Outlet Fluidic Sprinkler

为了探索全射流喷头均匀系数(CU)与分布系数(DU)之间的关系,选择圆形出口盖板的全射流喷头作为研究对象,设计了5个盖板出口直径,得出直径小于5.0 mm或大于7.0 mm时喷头不能工作。在工作压力为200、250和300 kPa下测量出喷头盖板直径为5.5、6.0和6.5 mm时的径向水量分布。布置方式选取为正方形,组合间距选取为7～15 m,采用三次样条插值法对组合CU和DU进行了仿真计算。结果表明:圆形出口盖板随着工作压力的增大,距喷头近处的水量增加,盖板出口的最优直径为6.0 mm。工作压力对组合CU和DU的影响并不明显;CU随组合间距的增加变化趋势是先相对平稳后急剧下降;DU随组合间距的增加经历了下降、增加和再下降的3个过程。通过对上述结果进行回归分析,初步提出了全射流喷头CU与DU之间的近似计算公式,为其在工程应用中提供理论基础。

To explore relationships between uniformity coefficient and distribution coefficient, the fluidic sprinkler with circular outlet cover plate （OCP） was chosen as the object. Five different OCP diameters were designed. The sprinkler cannot rotate when the diameter was less than 5.0 mm or more than 7.0 mm. Experiments were carried out under the operating pressure of 200 kPa, 250 kPa and 300 kPa and the radial water distribution of 5.5 mm, 6.0 mm and 6.5 mm, respectively. Square layout and combination spacing with 7 - 15 m were chosen. CU and DU were calculated by using the method of interpolation. The results showed that for the circular OCP, more water was distributed near the sprinkler with the increasing operating pressure. The optimal OCP diameter was 6.0 mm. Combination of CU and DU was slightly influenced by the operating pressure. As well as the increasing of the combination spacing, CU variation was stable firstly but sharply decreased later, and DU variation experienced three processes of becoming lower, becoming higher to attach the maximum value and becoming lower again for the reason of leakage spraying. The formula between CU and DU was put forward which was hoped to be a theoretical foundation for the project.