Perfil radial e uniformidade de precipitação do aspersor NaanDanJain 427, em função da regulagem do defletor

Abstract

R ESU M ONeste trabalho o objetivo foi avaliar o perfil radial e a uniformidade de distribuição de água do aspersor fabricado pela empresa NaanDanJain, modelo 427 1/2"M e bocal de 2,8 mm de diâmetro interno, operando com pressões de 150, 200, 300 e 400 kPa em cinco posições do defletor de ajuste (0, 20, 50, 80 e 100%). Para a determinação dos parâmetros avaliados utilizou-se o método da malha e, com o auxílio do aplicativo computacional CATCH 3D, calculou-se a sobreposição das lâminas de água com dez espaçamentos. Os resultados obtidos demonstram que o defletor de ajuste influencia o raio de molhamento e o perfil de distribuição enquanto a uniformidade de aplicação de água se mostrou como mecanismo importante, visto que permite comportamento diferenciado para o aspersor, garantindo ampla faixa de utilização do equipamento.Palavras-chave: uniformidade da irrigação, perfil de distribuição de água, desempenho hidráulico Radial profile and precipitation uniformity of sprinkler NaanDanJain 427, depending on the setting of the deflector A B ST R A C TThe study aimed to evaluate the radial profile and the uniformity of water distribution of sprinkler manufactured by the company NaanDanJain, model 427 1/2"M and nozzle with 2.8 mm of internal diameter, operating at pressures of 150, 200, 300 and 400 kPa and five positions of the deflector (0, 20, 50, 80 and 100%). For the determination of the parameters evaluated, the grid method was used and with the help of computer application CATCH 3D, overlapping layers of water depths was calculated with ten spacing. The results show that the deflector adjustment influences the radius of wetness and the distribution profile while the uniformity of water application showed as an important mechanism, since it permits different behavior for the sprinkler, ensuring wide track of utilization of the equipment.

Pressure compensation by a floppy disk in a sprinkler with rotation by centrifugal action

“…Martins et al . Therefore, the results observed with all nozzles are below this limit, corroborating the variation reported by Martins et al (2015), which was below 4% for the Super 10 sprinkler without compensation.…”

“…Increasing the working pressure of the sprinklers had a linear effect on the CV for all nozzles (Figure 2), whereby the CV increased with the working pressure. These results were also observed by Holanda Filho et al (2001) and Martins et al (2015). Table 4.…”

“…According to the classification, proposed by Solomon (1979) and ASAE (1999) ( Martins et al (2015), there is a positive linear relationship between pressure and CV, which was observed with the blue, yellow, green, and red nozzles. It is important that sprinklers present low CV values, because the uniformity of sprinkler manufacture also influences the uniformity of water distribution (KELLER; KARMELI, 1974).…”

“…Martins et al (2015) evaluated the Super 10 sprinkler without pressure compensator and found that flow increased with pressure.…”

“…Two coefficients are often used to determine uniformity: the CUC (CHRISTIANSEN, 1942) and the CUD. CUC is used to measure the spatial variability of water depth applied by irrigation systems, which is the main parameter determining the uniformity of application (MARTINS et al, 2012). The CUD measures the lowest quarter depth of the total area divided by the average depth applied (CRIDDLE et al, 1956).…”