EFFECT OF NOZZLE SHAPE AND PRESSURE ON DROPLET SIZE DISTRIBUTION

Document Type : Original Article

Authors

1 Prof of Agric. Eng., Dep. of Agric. Eng. , Faculty of Agriculture, Cairo University, Egypt.

2 Assoc. Prof of Agric. Eng. Dep. of Agric. Eng., Faculty of Agriculture, Al-Mansoura University, Egypt.

3 Agric. Res. Ins., Alexandria Branch, Alexandria, Egypt

Abstract

Droplet size data from the sprinkler (R.C. 160-S) fitted with nozzles shapes square, rectangle, triangle and circle were studded in this work.  A total 48 indoor tests were conducted. The pressure range was between 138 kPa (20psi) and 241.5 kPa (35psi) at 34.5 kPa (5 psi). Droplet size diameters were measured using the immersion method and Image Pro software. Nozzle pressure and shape had a major influence on droplet size. Higher pressure promoted smaller droplets over the entire application profile especially near the perimeter. Generally, the mean droplet sizes was larger for noncircular nozzles at a given distance from the sprinkler, but circular nozzle produced the largest droplet size at the outer perimeter of the pattern, that's because of long throw of circular nozzle than noncircular.

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