Study On Influence Factors Of Oscillation Performance Of Jet-pulse Tee

Pulse drip irrigation has the characteristics of strong anti clogging performance and high irrigation uniformity, which is widely concerned and applied by many countries around the world. Existing pulse drip irrigation generally through the electronic pulse device, the pulse solenoid valve or rubber, plastic film, spring and other elastic materials generated pulse flow, high cost, operation and maintenance of complex. The Jet-pulse Tee has the advantages of simple structure, low cost, high irrigation uniformity, long service life, etc., and is expected to solve the above problems. On the basis of previous studies, this paper further studies the influence factors of the oscillation performance of Jet-pulse Tee.Jet-pulse Tee is one of the key components of the drip irrigation system, which developed on the basis of the Coanda-Effect and the entrainment action. The stable oscillation of the Jet-pulse Tee is prerequisite to improve the work of drip irrigation system. The oscillation frequency, the amplitude of outlet pressure and the total pressure loss are important for drip irrigation system to improve performance. In this paper, CFD numerical simulation and experimental verification methods are used to study the oscillation performance of the Jet-pulse Tee. The main works and conclusions are as follows:(1) The internal flow and switching law of jet are simulated. According to the switching law, three top factors that affect the performance of oscillation are width difference, spliter distance and nozzle width(2) To investigate the effects of the geometry sizes and the inlet pressure, focus on the several factors of the oscillation frequency, outlet pressure, the influence degree and the influence of vibration, it is concluded the following conclusions: different sizes have different influences on oscillation performance, and the degree of influence are not the same. Affected by the nozzle width is the largest. Under the same conditions, the greater the nozzle width, the smaller oscillation frequency, the greater outlet pressure. Control tube length of Jet-pulse Tee has smalest influence on oscillation performance, oscillation frequency and outlet total pressure hardly change with the control tube length.(3) Jet-pulse Tee physical models were manufactured, and verified the theoretical research. The results show: theoretical research results are coincided with the experimental results, and can reflect the actual situation. The results of theoretical research has generic guiding significance for the Jet-pulse Tee for drip irrigation system.