Premium
EFFECT OF DE‐AWNING AND MOISTURE CONTENT ON SOME FRICTIONAL PROPERTIES OF PADDY
Author(s) -
ALIZADEH MOHAMMADREZA,
MINAEI SAEED
Publication year - 2012
Publication title -
journal of food process engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.507
H-Index - 45
eISSN - 1745-4530
pISSN - 0145-8876
DOI - 10.1111/j.1745-4530.2010.00602.x
Subject(s) - angle of repose , water content , friction angle , coefficient of friction , friction coefficient , moisture , internal friction , materials science , soil science , composite material , geotechnical engineering , environmental science , geology
One of the specific traits of Iran's local paddy varieties is the presence of awns at the tip of the lemma that cause difficulties in the grain flow through chutes and orifices. In this study, the effect of de‐awning and moisture content of paddy on the angle of repose, coefficient of internal friction and coefficient of mobility were evaluated as a function of moisture content in the range of 7–23% dry basis (d.b.). Results revealed that the effect of de‐awning and moisture content on frictional properties of paddy was highly significant ( P < 0.01). For awned paddy, the angle of repose increased from 37.42 to 45.70°; coefficient of internal friction increased from 0.453 to 0.574; the angle of internal friction from 24.37 to 29.85° and coefficient of mobility decreased from 0.415 to 0.335 as the paddy moisture content increased from 7.64 to 23.38% d.b. In the case of de‐awned paddy, the angle of repose increased from 34.46 to 42.68°; coefficient of internal friction from 0.427 to 0.512; the angle of internal friction from 23.11 to 27.10° and the coefficient of mobility decreased from 0.430 to 0.370 at same range of moisture content.PRACTICAL APPLICATIONS Knowledge of frictional properties is important in predicting the lateral pressure on a retaining wall in storage bins or design of bins and hoppers for gravity flow. The coefficient and angle of internal friction has applications in problems of flow of bulk granular materials encountered in problems flow of bulk granular materials equipment. To predict the flow ability of the grains through openings, it is important to determine the angle of repose of the materials. In design and optimization of paddy handling systems, especially de‐awner machine, dryer, huller and cleaning systems, it is important to obtain these frictional properties during paddy postharvest operations.