Determining Seed Cotton Mass Flow Rate By Pressure Drop Across a Blowbox

Accurate measurement of the mass flow of seed cotton is needed for control and monitoring purposes in gins.  Optical systems have been developed; however, coverage of large diameter pipes requires multiple sensor units and greater cost.  Other systems have been developed based on the change in static pressure in a vertical section of pipe or a change in velocity.  However, these other pressure measurement-based systems have not demonstrated the needed accuracy.   A prototype mass flow measurement system was installed in a small-scale pneumatic conveying apparatus for seed cotton.  Two cultivars, two moisture content levels, three feed rates, three fan speeds, and two pipe diameters were tested to determine the accuracy of this system.  Seed cotton moisture and fractionation samples were collected from each test lot, and seed cotton weight and conveying time were recorded to determine actual mass flow rate.