竖管灌水器入渗特性影响因素分析

摘要

Vertical tube emitter is a new type emitter applied for sub-irrigation system,in order to analyze the importance for cumulative infiltration of silt loam by influence factors which including pressure head,diameter of vertical tube,initial soil moisture content and soil bulk density.So as to the laboratory test have the accuracy,universal and representativeness,the nine groups of the experimental schemes designed based on the orthogonal experimental design table L9 (3 4 ).In ad-dition,the experiment of effects on sandy loam cumulative infiltration with influence factors of pressure head and diameter of vertical tube carried out.A Mariotte bottle used to regulate the pressure head.The total infiltration time was 7h for every treatment of silt loam and 5h for sandy loam,and the interface-between soil and outlet of emitter—was buried 20cm for every test.Ac-cording to the results of experiments for silt loam,used grey correlational analysis method to cal-culate incidence degree between influence factors and cumulative infiltration.The incidence de-gree pointed out that pressure head was the main influence factor and the order of factors with in-cidence degree was pressure head>diameter of vertical tube>initial soil moisture content>soil bulk density.The experimental results of sandy loam showed that pressure head and diameter of vertical tube had a positive effect on cumulative infiltration;with the increasing of pressure head and diameter of vertical tube the rangeability of cumulative infiltration decreases.This research has an important significance on further study on infiltration law of vertical tube emitter.%竖管灌水器是一种用于地下灌溉系统的新型灌水器，本文研究影响竖管灌水器入渗特性的四个因素：压力水头、竖管灌水器直径、土壤初始含水率和土壤容重等，为了研究这些因素对粉质壤土累积入渗量的影响程度，采用正交试验安排试验方案；而对于砂质壤土主要研究压力水头和竖管灌水器直径对累积入渗量的影响。根据竖管灌水器入渗试验结果，采用灰色关联度分析对影响粉质壤土累积入渗量的影响因素进行关联度计算，表明压力水头对入渗量的影响起主导作用，其次依次为竖管灌水器直径、土壤初始含水率、土壤容重；砂质壤土试验结果表明：压力水头和竖管灌水器直径与累积入渗量呈正相关关系，但随着压力水头和竖管灌水器直径的增大，累积入渗量的增大幅度减小。这一研究结果对进一步研究竖管灌水器入渗规律具有重要意义。