Effect of dynamic pressure on emitter clogging in drip irrigation system: The perspective of multiple fouling

Enhancing the anti-clogging ability using dynamic pressure (DP) is an effective measure to improve the water use efficiency of drip systems. However, the response patterns of multiple fouling inside emitters to DP require further investigation. Therefore, a laboratory experiment was conducted to evaluate the effects of DP on the clogging performance and fouling characteristics of drip tapes, with constant pressure (CP) of 100 kPa as the control group. DP was applied in a trapezoidal waveform with a baseline pressure of 100 kPa, an amplitude of 30 kPa, and a cycle time of 90 s. The experiment spanned 64 days. Two types of non-pressure-compensating drip tapes and one type of pressure-compensating drip tape were tested, with performance evaluations conducted on 10 sampling points from each tape. The results demonstrated that, compared to CP, DP suppressed the fouling dry weight (DW) by 54.8 % (p < 0.01). And DP strikingly raised the discharge ratio and variation (Dra) by 32.2 % and Christiansen’s irrigation uniformity (CU) of drip system by 21.8 %. Meanwhile, DP effectively alleviated the inhibitory effects of fouling on Dra and CU. Additionally, there were markedly mutual promotion effects among multiple fouling (p < 0.01). DP inhibited the accumulation of particulates (59.7 %), precipitates (55.7 %), and biofouling (26.7 %) (p < 0.05) thereby improving Dra and CU. Overall, DP is a promising operational strategy to mitigate clogging for multiple fouling, thereby enhancing the water utilization efficiency of drip systems.