Performance hidráulica de microgotejadores Kafit novos e usados.

Abstract

The hydraulic perormance of new and 2,5 years used katif emitter type (3,75 1/h) was evaluated in this study. The analysis was based on the coefficients of manufacturing variation and use, the dicharge and pressure relation ship, and the application uniformity. Several mathematical relationships were tested on measured discharge and pressure data fitting. For both used and new emitters, the best fitting was given by the Hoerl module function ( r2 for new and used emitters were, respectivelly, 0.9744 and 0.9899), while the potential function resulted on the worst fitting ( r2 for new and used emitters were, respectivelly, 0.2324 and 0.1087). The new emitters presented a better application uniformity and less sensitivity to pressure variations. This shows that the self-compensanting pressure ability of this kind of emitter degenerates with time. The hysteresis phenomenon was verified on the hydraulics of these emitters. Inaddition, this study shows evidencies of a new kind of variation on the emitter hydraulics, related to the working machanism of the self-compensation, which may, also, compromise the application uniformity of the system.