Determinação do bulbo molhado em gotejamento superficial e subsuperficial para Cachoeira do Sul - RS

Abstract

The dynamics of the bulb formed by drippers in a source-point application is important for the sizing of projects. As the increasing of installation of subsurface drip irrigation, quantification of the bulb at this condition is fundamental for the success of the irrigation enterprise. Therefore, the purpose of this work was to evaluate bulb dimensions and wetted area as a function of flow, both on surface and in subsurface application, at Argisoil in the municipality of Cachoeira do Sul - RS. Experimental design was a completely randomized in a double factorial, composed by five emitter flows (1 to 5 L/h) and the two emitter positions (surface, and 0.1 m of depth), measuring the bulb at various depths, besides the horizontal area and the depth reached. There was no interaction between factors, hence the designers just need one condition for sizing the system. Surface bulb diameter, maximum diameter, and depth related to flow by a potential equation, while the area adjusted to the linear model. The maximum bulb diameter tends to be obtained on surface, and is sufficient for the characterization of the wetted area, even for subsurface application.