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 anagriculturalimplement includes the steps of:calibrating a pressure drop across a known distance in an air line at a numberof air flowrates;metering a product at a desired application rate into the air line at aselected air flow rate;establishing a pressure drop across the known distance at the selected airflow rate, whilethe product is being metered;calculating a specific pressure drop by dividing the established pressure dropby thedetermined pressure drop;ascertaining the values of parameters A and B using the mathematicalexpression:.alpha.=1+Aµ+B.sqroot.µwhere:.alpha. = specific pressure drop;µ = mass loading ratio; andA and B = parameters based on measured data for the specific product beingapplied; andestimating a mass flow rate of the product being applied.