Abstract
Limited advancement of direct injection pesticide application systems has been made in recent years, which has hindered further commercialization of this technology. One approach to solving the lag and mixing issues typically associated with injection-based systems is high-pressure individual nozzle injection. However, accurate monitoring of the chemical concentrate flow rate can pose a challenge due to the high pressure, low flow, and changing viscosities of the fluid. A methodology was developed for recalibrating high-pressure chemical concentrate injectors to compensate for fluid property variations and evaluate the performance of this technique for operating injectors in an open-loop configuration. Specific objectives were to (1) develop a method for continuous recalibration of the chemical concentrate injectors to ensure accurate metering of chemicals of varying viscosities and (2) evaluate the recalibration method for estimating individual injector flow rates from a system of multiple injectors to assess potential errors. Test results indicated that the recalibration method was able to compensate for changes in fluid kinematic viscosity (e.g., from temperature changes and/or product variation). Errors were less than 3.4% for the minimum injector duty cycle (DCi) (at 10%) and dropped 0.2% for the maximum DCi (at 90%) for temperature changes of up to 20°C. While larger temperature changes may be expected, these test results showed that the proposed method could be successfully implemented to meet desired injection rates. Because multiple injectors would be used in commercial deployment of this technology, a method was developed to calculate the desired injector flow rate using initial injector calibration factors. Using this multi-injector recalibration method, errors ranged from 0.23% to 0.66% between predicted and actual flow rates for all three injectors.
Document Type
Article
Publication Date
2016
Digital Object Identifier (DOI)
https://doi.org/10.13031/trans.59.11521
Related Content
The information reported in this article (No. 15-05-074) is part of a project of the Kentucky Agricultural Experiment Station and is published with the approval of the Director.
Repository Citation
Luck, Joe D.; Shearer, Scott A.; Luck, Brian D.; and Sama, Michael P., "Recalibration Methodology to Compensate for Changing Fluid Properties in an Individual Nozzle Direct Injection System" (2016). Biosystems and Agricultural Engineering Faculty Publications. 140.
https://uknowledge.uky.edu/bae_facpub/140
Notes/Citation Information
Published in Transactions of the ASABE, v. 59, issue 3, p. 847-859.
© 2016 American Society of Agricultural and Biological Engineers
The copyright holder has granted the permission for posting the article here.