滴灌技术是农业可持续发展的重要途径,但提高滴灌滴头水力性能的存在诸多难题,滴灌滴头水力性能优化是滴灌技术不断发展的需要。流量系数和流态指数是决定滴头水力性能的两个主要参数,如何提高滴头的水力性能已成为近年来的研究热点,大量研究只是对滴头水力性能进行了单目标分析,滴头水力性能优化涉及到流量系数和流态指数与滴头流道结构参数变量之间的权衡,因此流量系数和流态指数同步优化解决方案显得非常重要。提出基于流量系数和流态指数为目标函数的滴灌滴头水力性能多性能指标(MCPI)优化方法,将田口方法和模糊逻辑相结合,测试和优化滴头水力性能。结果表明,流道宽度、流道深度、流道转角和流道单元数对MCPI影响极显著,它们对MCPI贡献率超过85%,与此同时流量系数和流态指数分别改善了7.91%和6.75%,优化后的流量系数k=0.128、流态指数x=0.506。以最优因素水平组合W1L1D3θ2N3做滴头水力性能试验,实际测得的流量系数k=0.126、流态指数x=0.504,与优化推理值符合较好。
The proposal of drip irrigation technique to enhance irrigation efficiency is the key problem for sustainable development of agriculture, but it is very challenging because of the inherent fluctuations of the hydraulic performance of drip emitter (HPDE). Flux coefficient and flow index are the two critical factors attributing to the hydraulic performance of drip emitter. A lot of researches have carried out study on the hydraulic performance of drip emitter only based on single objective optimization of HPDE, however, simultaneous optimization solutions on the multiple characteristic performance indices (MCPI) and the corresponding effects on HPDE still remain underexplored. Based on MCPI, HPDE with labyrinth channels was optimized by combining the Taguchi method and fuzzy logic. The analysis results of variance for MCPI show that factors including width, depth, angles and unit numbers had significant effects on MCPI, accounting for over 85% of total variations of MCPI. The optimal factor combination can be determined as W1L1D3θ2N3. Compared with the 1st time optimized result, MCPI of the optimal condition was improved by 8.04%, meanwhile, the flux coefficient of 0.128 and flow index of 0.506 were improved by 7.91% and 6.75%, respectively. Finally, the experimental tests based on factor combination of W1L1D3θ2N3 was conducted to investigate the optimal mechanism, which showed that the flux coefficient was 0.126 and the flow index was 0.504, indicating that MCPI was a promising processing method for HPDE.