Development of a microsprinkler system with microtubes for vegetable crops

Author(s)

Alexsandro Claudio dos Santos Almeida

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
• Defense date: 2009-02-02

Examining board members

Tarlei Arriel Botrel; Rubens Duarte Coelho; Fernando Campos Mendonça

• Advisor: Tarlei Arriel Botrel

Abstract

The technology innovation is the way most feasible to develop a sustainable agriculture in Brazil. In this way, the country will have to invest in sectors which can produce innovation technologies, adequate to specific conditions and with cost more accessible, to replace the dependency from imported products. In this context, this work had to objective to develop microsprinkler spinner deflector with good distribution uniformity to work with overlap and adapt the microtubes techniques developed by Almeida, Botrel e Smith (2008) to commercial microsprinkler. Experiments in laboratory and field were carried out at Escola Superior de Agricultura Luiz de Queiroz, University of Sao Paulo, Brazil, where were developed and evaluated the microsprinkler prototypes and evaluated discharge uniformity along of lateral line with commercial micro-sprinklers and microtubes as emitter. In the development of the microsprinkler prototypes were tested a lot of materials and processes. The materials utilized were clay, biscuit, plaster, modeling mass, talc stone, PVC, technyl, teflon and polypropylene. The processes were mechanic tournament, modeling and the rapid prototyping. The performance of micro-sprinkler irrigation system with microtube emitters was evaluated both laboratory and field tests. Microtube pressure-length-discharge relationship was determinate and discharge distribution uniformity along of lateral line was evaluated. Uniformity Coefficient from Christiansen (CUC), Distribution Uniformity (DU) and Uniformity Statistic (Us) were used as indicators for evaluation of performance of emitters. Among the tested materials, the PVC and the technyl showed more facility in the deflector build, however, the PVC was choose due the better finish small channels. The rapid prototyping process provided the better finish in the deflector. In the proposed overlap, the better overlap arrangement occurred with the prototype of 6 channels with 350 and two channels differentiated. The developed prototypes which not worked and the adjustments did in them, contributed significantly to reach positive results in prototypes. The deflector geometric, angle and number of channels affected directly the performance of microsprinklers, nevertheless, the biggest angle showed water distribution uniformity more satisfactory. The utilization of microtubes techniques adapted well in conventional microsprinklers, and provided good uniformity in the discharge in lateral line. (AU)