无压条件下微孔陶瓷灌水器入渗特性模拟

为探究微孔陶瓷灌水器在地下灌溉的入渗特性,基于土壤水动力学原理,在前人对微孔陶瓷灌水器周围土壤水势分析的基础上,建立了无压条件下微孔陶瓷灌水器在土壤中的出流模型,并通过室内土桶试验验证了模型的准确性。结果表明:该文提出的出流模型可以较好地模拟无压条件下微孔陶瓷灌水器土壤中的出流现象。在0m工作水头下,灌水器周围土壤含水率变化是造成灌水器流量变化的根本原因,土壤含水率较低时,灌水器可以较大流量出流;随着灌溉的进行,土壤含水率逐渐增加,使得灌水器流量减小;当土壤含水率达到饱和后,灌水器就会停止出流。而当土壤水分耗散时,灌水器又可恢复出流,灌水器出流量与土壤水分耗散量基本相当,因此灌水器出流可以实时补充土壤水分。本研究可为微孔陶瓷灌水器的推广应用提供参考。

Simulation of infiltration characteristics of porous ceramic emitter under non-pressure condition

In order to research the infiltration characteristics of porous ceramic emitter buried in soil, a flow model of porous ceramic emitter under non-pressure condition was constructed on the base of the principles of soil water dynamics and previous studies about water soil potential around the porous ceramic emitter. An indoor soil bin experiment was carried out to verify the accuracy of the model. The results indicate that the model presented in this paper could be used to simulate the flow phenomena of the porous ceramic emitter under non-pressure condition. The predictions of the model are consistent with the experimental data. When the working pressure is 0 m, the basic cause of soil water content change is the change of the emitter discharge change,which decreases gradually with the increase of water contents around the emitter. When the soil water content is saturated, the emitter discharge would be stopped. When the soil moisture is dissipated, the flow would recover from emitter again, and the discharge is approximately equal to soil evaporation capacity. Therefore, the emitter discharge would supply the soil water content in time. This paper provides a reference for the popularization and application of porous ceramic emitter.