Simulation of Spraying Process in Lateral VRI Sprinkler System based on PWM

• Main Authors: Zhou Zhiyu, Tao Shuai, Mo Jinqiua
• Format: Article
• Language: English
• Published: EDP Sciences 2018-01-01
• Series: MATEC Web of Conferences
• Online Access: https://doi.org/10.1051/matecconf/201824603012

Lateral VRI sprinkler system is widely used to improve water productivity nowadays. And Pulse width modulation (PWM) technique is applied to control flow rate of each sprinkler. Uniformity and accuracy of application are main indexes to evaluate performance of lateral VRI sprinkler system. Traditional approach of measuring uniformity and accuracy is catch can trials. However, the data obtained is sparse and data collection takes time and labour. In this article, a simulation algorithm is designed to find the effects of PWM parameters and speed of VRI sprinkler system on spraying results of Nelson R3000 sprinkler efficiently. Experiments indicate that PWM duty cycle affects water depth proportionally while speed has an inverse proportional effect. And indistinctive reduction of water application is found as PWM period increases. A compensation method is also put forward to minish application error caused by PWM duty cycle, period and speed. It is also found that lower speed or shorter period leads to larger water depth error but higher application uniformity. Duty cycle has insignificant positive influence on application uniformity but barely on water depth error. Besides linear transition of water depth is observed when a sprinkler passes through two different management zones in the moving direction.