Semi-empirical mass flow model and calibration method for undeveloped flow regions in an air seeder

摘要

A method of determining a mass flow rate of product being applied with an agricultural implement includes the steps of:calibrating a pressure drop across a known distance in an air line at a number of air flow rates;metering a product at a desired application rate into the air line at a selected air flow rate;establishing a pressure drop across the known distance at the selected air flow rate, while the product is being metered;calculating a specific pressure drop by dividing the established pressure drop by the determined pressure drop;ascertaining the values of parameters A and B using the mathematical expression:α=1+Aμ+B√{square root over (μ)} where: α=specific pressure drop;μ=mass loading ratio; andA and B=parameters based on measured data for the specific product being applied; andestimating a mass flow rate of the product being applied.