CRITERIA AND PROCEDURES FOR EVALUATION OF SOLIDS MIXING IN AGRICULTURAL SPRAYER TANKS

An agitation effectiveness index (AGEF) was defined to help evaluate the effectiveness of hydraulic agitation systems in agricultural sprayer tanks regardless of tank size and shape. AGEF was calculated based on three measured mixing criteria: particle deposits remaining on the bottom of the tank following the application, the coefficient of variation of the mixture concentration in the line to the boom, and the ratio of maximum deviation of the mixture concentration at the tank outlet to the mean concentration measured during the application. The ratio of AGEF to required hydraulic power of the agitation system, named Power Ratio, was also used as another parameter to evaluate sprayer tank agitation systems. The method suggested in this article was applied to evaluate a large number of agitation experiments conducted as well as a previous researcher’s unevaluated agitation data in order to show its applicability. Use of this method is limited to solid-liquid type mixtures in order to determine the suspension uniformity achieved with hydraulic agitators. Kaolin clay was used as solid particles since this is a common carrier for wettable powder and granular pesticides. The results showed that AGEF was sensitive enough to enable reasonable comparisons and that this method can be used to standardize minimum requirements of a hydraulic jet agitation system. AGEF and Power Ratio provided a novel approach to identify efficient agitation systems with low energy requirements.