Comparação das velocidades terminais para grãos de feijão em secção de coluna de queda circular e quadrada de diferentes tamanhos.

Abstract

The objective of this work was to determine the terminal speed of the beans with 13,80% of humidity. This parameter was determined with an equipment of circular section column of fall and square shaped of 60, 50, 40, 30 and 20 mm of measure (diameter and side), measuring it terminal speed with an anemometer, meeting 12,75 ± 0,472; 8,74 ± 0,375; 4,88 ± 0,199; 2,64 ± 0,255 and 1,77 ± 0,313 m s-1, in circular column and 12,99 ± 0,433; 10,4 ± 0,414; 6,72 ± 0,248; 4,91 ± 0,431; e 2,09 ± 0,366 m s-1 in square shaped column. It was concluded that: a) the terminal speed in free fall was obtained only in the column of square shaped section of 60 mm of diameter; b) the bigger terminal speed was gotten with the column of square shaped section; c) the values gotten for terminal speed presented a dependence of the size of the section, diminishing with the reduction of the size of this.