**3. Results**

#### *3.1. Spray Droplet Characterization*

The customization of the micro-emitter resulted in reduced cone angle and wetted parameter and enhanced vertical throw for modified irrigation micro-emitter (concavity = 50◦, cone angle = 95◦, vertical throw = 640 mm and wetted diameter = 1520 mm) (Figure 1c,e) compared to the original micro-emitter (cone angle = 150◦, vertical throw = 320 mm and wetted diameter = 2100 mm). Furthermore, modified micro-emitters produced a medium droplet size spectrum (DV0.5 = 256.2 μm), while a hollow cone nozzle resulted in a fine droplet size spectrum (DV0.5 = 130.9 μm) (Table 3). The pressure data indicate a marginal drop of 2 kPa between the main inlet and return outlet for both treatments. Such a small pressure drop eliminates the chances of variation in droplet characteristics due to reduction in pressure along the spray line.

**Table 3.** The volumetric droplet size distribution of the modified irrigation micro-emitter and hollow cone nozzle.

