Numerical simulation of clogging of two types of emitters with similar properties

Abstract

The benefits of drip irrigation are numerous and include water savings, control of fertilizer applications, and improved water and energy use efficiency of irrigation. In these systems, the emitter is the most vulnerable component to clogging, which in critical states can cause a reduction in performance and shorten the life of the distribution system. It can also have several impacts on water, its economy, and its wastage. In the absence of adequate filtration and when the flow is through the narrow labyrinth channel of the emitter, clogging can be created by continuous deposition of solid particles, organic matter, dissolved salts, chemical precipitates, bacteria, and other impurities. It is obvious that it is impossible to physically visualize the hydraulic behavior of the flowing water in the labyrinths. However, due to the increasing performance of computational tools and simulation software, it is possible to simulate this flow through Computational Fluid Dynamics (CFD), which has become one of the main techniques for describing the flow and deposition of the solid phase inside the emitter. This study aims to numerically simulate the behavior and the flow of the fluid inside two emitters, widely used in the industry, with different types but approximately identical flow rates. The fluid takes in its flow an inert solid suspension of fixed concentration. One of the emitters is compensating‐pressure, and the other is non‐compensating‐pressure; the numerical simulation model used is the RNG κ‐ε two‐phase model. The results showed that the regions affected by clogging are mainly the corners of the labyrinth channel and the recirculation vortex zones. The trajectory field plot reveals that as the clogging increases, the serpentine fluid threads become thinner.