Influence of Orifice Group Geometric Parameters on the Hydraulic Performance of Porous Microsprinkling Hoses Using Orthogonal Design

The flow uniformity within an orifice group is crucial for the irrigation performance of porous microsprinkling hoses. This study investigated the hydraulic performance of microsprinkling hoses with a single-row oblique circular orifice arrangement by systematically evaluating five structural parameters, i.e., folded diameter (DN), orifice diameter (d), number of orifices per group (n), orifice inclination angle (α), and edge distance (s′), using an orthogonal array design (25 configurations) under multiple operating pressures. Group flow rate, within-group flow uniformity, and the pressure change across the orifice group (Δp) were quantified to assess the relative importance of operating pressure and geometric parameters within the investigated domain. The results show that operating pressure increases group flow rate, whereas its influence on within-group uniformity and Δp is negligible compared with the geometric parameters within the tested pressure range. Among the structural parameters, d and n are the key factors governing group flow rate, DN and d dominate within-group flow uniformity, and n and DN dominate Δp. The highest within-group flow uniformity among the tested levels was obtained at DN=50 mm, d=1.5 mm, n=11, α=60°, and s′=2 mm, while the smallest Δp among the tested levels occurred at DN=50 mm, d=0.8 mm, n=8, α=30°, and s′=8 mm. These findings provide an experimentally grounded, multimetric basis for parameter selection and design screening of similar microsprinkling hoses within the investigated parameter levels and operating pressures.