Research Of Pesticide On-line Mixing Method For Engine Powered Knapsack Sprayer

The pesticide online mixture device can mix the pesticide automatically toseparate the pesticide and the user, which avoid the arbitrary use of pesticide andprotect the pesticide users. As a result, the knapsack sprayer and its online pesticidemixture device was studied to support the online pesticide mixture study.First of all, the jet-type pesticide mixture theory was studied and the feasible mixturemechanism for knapsack sprayer was proposed. The basic performance equation ofjet-type pesticide mixture device in the system of non-isodense was established. Theperformance influencing factors were analyzed and concluded as follows: hybird tubediameter, nozzle diameter，burner cap were the major performance factor of jet-typepesticide mixture device.A series of small-flow jet-type pesticide mixture devices for knapsack sprayerwere designed. The bench and prototype were tested to determine the structure ofoptimal pesticide mixture device and the loss coefifcients’ values of local resistanceand on-way resistance in the basic performance equation of jet-type pesticide mixturedevice. It was found that the pressure of sprayer was higher than the pressure oftesting bench, the flow rate of nozzles was lower, which lead to the smaller size of thenozzle size to inhale the pesticide. As a result, the nozzle was required to be processedwith higher accuracy.Atfer testing the nozzle’s loss coefifcients’ values of local resistance, it wasconcluded that the pressures of jet nozzle outlet, pesticide inhaling tube’s outlet andthe mixing tube’s outlet were different greatly. Meanwhile, the jet nozzle outletcouldn’t be coincide with the mixing tube inlet’s end face. Otherwise the pesticideinhaling resistance of the pesticide online mixture device would be great.