Aiming at the influence of labyrinth channel wall topography on the flow behavior and adhesion between particles and channel wall under the condition of silt-content irrigation
the emitter channels of different wall topography are chosen
and the hydraulic performance tests and the visual experiments on particle-wall adhesion are conducted via particle image velocimetry(PIV). The computational fluid dynamics is utilized to numerically simulate the flow field. The results show that the higher the wall roughness(the value is 10% of the hydraulic diameter)
the greater the resistance coefficient will be. That is
under the same pressure
the smaller the outlet flow rate
the more easily the particle-wall adhesion occurs. Wall roughness affects particle concentration distribution
and the particle velocity near the roughness elements is low
resulting in emitter clogging.
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references
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