ADVANCED METHODS TO DEVELOP DRIP EMITTERS WITH NEW CHANNEL TYPES

Abstract

Because of their micro-scale and complex structure, the development cost of new drip emitters is high. To reducethe cost, some advanced technologies, such as computer-aided design (CAD), computational fluid dynamics (CFD), rapidprototyping (RP) and rapid tooling (RT) were used to establish a rapid method for emitter development. The emitter channelwas designed using a three-dimensional parameterized CAD model. Then the flow within the channel was simulated usingCFD, which provided visual results of pressure and velocity distributions. Moreover, the discharge and flow exponent of theemitter were also obtained from the CFD simulations. Verified by the simulation results, several types of emitters werefabricated using RP/RT without making an experimental steel mold or amplifying emitter models. Using these prototypeemitters, the performance experiments of structural finalization were done directly. Results showed that the deviationsbetween the measured and simulated discharges were less than 5%. Using a comprehensive analysis of the simulated andmeasured results, a steel mold for one of the emitters with optimum performance was manufactured. The measuredperformance of the plastic emitters fabricated using the mold was close to the results of the simulations and prototype tests,which indicating a successful steel mold for volume production. Taking the eddy-channel emitter developed here as anexample, a comparative cost analysis showed that both the cost and time of emitter development were reduced by 50%.