Assessment of head loss equations developed with dimensional analysis for micro irrigation filters using effluents

Several equations have been developed using dimensional analysis to determine the head loss in the filters commonly used in micro irrigation systems. The variables included in these existing equations were established using dimensional analysis and Buckingham’s theorem. A filtration experiment using effluents with sand, screen and disc filters was carried out for up to 2000 h to obtain data to enable the developed equations to be correlated. A new equation that included head loss, filtration velocity, concentration of total suspended solids (TSS) in the filter influent, water density and viscosity, and inside diameter of the inlet and outlet pipes as variables showed similar and satisfactory predictions to as previously developed equations that required the use of more variables.