Discussion of 'Rapid Evaluations of Anticlogging Performance of Drip Emitters by Laboratorial Short-Cycle Tests' by Quingsong Wei, Yusheng Shi, Gang Lu, Wenchu Dong, and Shuhuai Huang

摘要

The discusser appreciates the authors for presenting an experimental procedure (Wei et al. 2008) to rapidly evaluate the anticlogging performance of three types of drip emitters by implementing short-cycle tests. Through the paper, a modified form of the Christiansen's uniformity coefficient (C'_U) [Eq. (4) instead of traditional Eq. (3)] taking into account the relative effect of emitter clogging, was also derived by replacing the average discharge by the nominal discharge. The proposed rapid evaluation procedure gives an opportunity to designers to describe the clogging status of some emitters regarding the critical level of clogging ([logging rate, C_r by Eq. (1)] (illustrated by Fig. 5 of the paper), and also sensitively determine the real level of distribution uniformity (Figs. 9 and 10) of drip irrigation systems, in practice. Obviously, as the degree of plugging effect increase, the level of water application uniformity decrease within drip irrigation system.