Optimal structure selection of emitter flow path in drip irrigation system with inferior water resources

ABSTRACT The fundamental solution to the problem of emitter clogging is to explore the optimal structure design of emitter and improve its anti-clogging ability. The research objective was to select the optimal structural form of the emitter flow path in drip irrigation systems using inferior water sources, which can provide theoretical support for improving the anti-clogging ability of the emitter itself and designing new emitter products. The selection of the flow path structure of the emitter has not been conducted on the basis of determining the appropriate simulation model with the condition of complex water quality. Therefore, the appropriate internal fluid movement model of the emitter was determined, the hydraulic performance and anti-clogging performance of the five nationally and internationally representative flow path structures were comprehensively evaluated, and finally the optimal structure of the emitter flow path was determined. The research results indicated that RNG k - ε model was the most suitable to simulate the flow field in the emitter by comprehensive analysis of the gap between simulated values and the measured values, the calculation accuracy and computational efficiency. The fractal flow path was relatively optimal for hydraulic performance and for anti-clogging performance. This study can provide theoretical support for improving the anti-clogging ability of the emitter itself and the design of the new emitter product. RESUMO A solução fundamental para o problema do entupimento do emissor é explorar o projeto ideal da estrutura do emissor e melhorar sua capacidade anti-entupimento. O objetivo da pesquisa foi selecionar a forma estrutural ideal do caminho de fluxo do emissor em sistemas de irrigação por gotejamento utilizando fontes de água de qualidade inferior, proporcionando suporte teórico para melhorar a capacidade anti-obstrução do próprio emissor e para o projeto de novos produtos de emissores. A seleção da estrutura do caminho do fluxo do emissor não tem sido conduzida com base na determinação do modelo de simulação apropriado com a condição complexa de qualidade da água. Para tanto, determinou-se o modelo de movimento interno do fluido adequado do emissor, e avaliou-se de forma abrangente o desempenho hidráulico e o desempenho anti-entupimento das cinco estruturas representativas da trajetória de fluxo no país e no exterior, e finalmente determinou-se a estrutura ótima da trajetória de fluxo do emissor. Os resultados da