Abstract:An emitter with labyrinth channel was used as the study model, the channels were designed by using a full factorial experiment for two factors with four levels, the liquidsolid twophase flows in them were simulated numerically by means of Fluent 6.3. Influences of tooth angle and pitch on the hydraulic and anticlog performances of emitter were explored. The results showed that discharge coefficient can be correlated to tooth angle and pith with a positive relationship; moreover, the discharge coefficient increases with increasing tooth angle and pitch. The influences of tooth angle are more complicated; when the tooth angle is more than 120°, the flow regime index decreases initially then increases with increasing tooth pitch; when the tooth angle is less than 120°, however, the index decreases firstly, then increases with increasing tooth pitch. It was proposed that the anticlog performance can be analyzed by certain range of suspended sand particle concentration. The level of the maximum particle concentration in the channel is not completely proportional to the size of the area of high concentration, but the higher the maximum concentration, the greater chance the suspended particles to gather together and the greater the probability that a local sediment happens; at last the size of the area of high concentration gets larger and the emitter becomes clogged more easily.
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