農藥施用飄積現象之研究Ⅰ－液壓噴嘴噴霧粒徑分佈與風速的影響

The Study on Drift Phenomena for Pesticidal Spraying (I)-The Effect of Particle Distribution and Wind for Nozzle Spraying

盛中德(Chung-Teh Sheng) ； 黃明仕(Mins-Shi Hwang)

《農業機械學刊》 3卷1期 (1994/03) Pp. 57-66

https://doi.org/10.30062/JAM.199403.0005

摘要

本試驗採用矩形截面風洞與鋸齒形收集床進行液壓噴嘴飄積現象之研究。噴嘴之粒徑分佈資料，使用雷射粒徑分析儀(Malvern 2600)予以量測。量測結果顯示霧粒之粒徑分佈特性與噴嘴型式、藥液之供給壓力有顯著的關係：體積平均粒徑(VMD)與Sauter氏平均粒徑(SMD)皆隨著供給壓力的提高而下降，二者在對數座標上與供給壓力呈直線負相關，相關係數高於0.98。小於154μm之小液滴所佔的噴霧體積比率(DV154)則隨著SMD的減小而增加。DV154與SMD間呈負相關，而DV154可用來做爲不同型式噴嘴進行建立飄積通用模式的參數。
本試驗分別對粒徑分佈與風速進行飄積測試，並以噴霧沉積體積累積率與分佈中心飄移距離來描述飄積現象，試驗結果顯示風速愈大，則飄積現象愈明顯，SMD愈大則飄積現象愈不顯著。

關鍵字

液壓噴嘴 ； 風洞 ； 飄積

並列摘要

A wind tunnel with rectangular section and a corrugated sheet with sharp groove were adopted in this study to discover the drift phenomenon of spraying. The Malvern 2600 Particle Size Analyzer was used to determine the droplets size distribution of a nozzle.
The experimental results show the characteristics of the droplets are related to the type of nozzle and the injection working pressure of liquid. The volumetric median diameter (VMD) and Sauter mean diameter (SMD) are decreased following the increase of liquid pressure. In logarithmic coordinates, VMD and SMD have the negative relationship with liquid pressure, and the correlation coefficient is 0.98. DV154 is defined as the volumetric percentage of the droplets of which diameters are less than 154um. The value of DV154increases as SMD decreases. And DV154 can be used as a parameter of the drift model for different types of nozzle.
The experiments has been tested the degree of drift to the droplet size distribution and wind speed. The percentage of volumetric deposition of spraying and the distance between the distribution centers were selected to represent the degree of drift. The experimental results show the increases of wind speed will intensify the degree of drift phenomenon. The increase of SMD will diminish the drift phenomenon.

並列關鍵字

Spraying nozzle ； Tunnel ； Drift