Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/15/2001
Publication Date: 3/15/2002
Technical Abstract: Peanut curing wagons have typically been constructed using perforated metal floor with 23% open area (O.A.). Recent designs for larger peanut drying trailers have used perforated metal with 40% O.A. However, no data has been collected to determine the effect of the different O.A. on total airflow or the distribution of airflow through the peanuts. Six 6.4-m peanut drying wagons were loaded with dry farmer stock peanuts at a local peanut processing facility. Three wagons had floors with 23% O.A. and three had floors with 40% O.A. Peanuts were leveled on each trailer and peanut depth ranged from 114 to 130 cm. A 76-cm diam., 1750 rpm, 4-blade vane axial fan, dryer with a 91-cm long straightening inlet transition was connected to each peanut drying trailer. The rated airflow capacity of the dryer was approximately 300 m3/min at 12 mm H2O. Total airflow was measured using a pitot tube traverse across the inlet transition. Static pressure was measured in the wagon plenum using a U-tube manometer. The top of the trailer was divided into 40 sections using a 5 x 8 cell grid. The airflow through each grid cell was measured using a vane anemometer mounted on a conical transition placed in the center of each grid cell. No significant differences in static pressure, total airflow, [or] airflow distribution due to the percent O.A. of the perforated drying floor were detected. The average static pressure observed for wagons with the 23 and 40% O.A. was identical at 12.4 mm H2O. Total airflow measured at the fan inlet averaged 283 m3/min for the 40% O.A. trailers compared to 277 m3/min for trailers with 23% O.A. Specific airflow averaged 9.42 m3/min/m3 for the peanut wagons with 23% O.A. with a standard deviation 1.13 m3/min/m3. Similarly, the drying wagon with a 40% O.A. floor had an average specific airflow of 9.50 ± 1.12 m3/min/m3. Contour plots indicated that some variations exist within the trailer due to position and possibly concentration of foreign material. Possible differences due to fan performance will be discussed.