Coefficient of Friction of Pulse Grains on Various Surfaces at Different Moisture Content

Abstract

This study was carried out to determine the effect of moisture content on coefficient of friction of chickpea, khesari, blackgram, cowpea, fieldpea, mungbean, and lentil. The material generally moves or slides in direct contact with trough, casing, and other components of the machine. Various parameters affect the power requirement to drive the machine. The frictional losses are one of the factors, which must be overcome by providing additional power to the machine. Four levels of moisture contents of chickpea, khesari, blackgram, cowpea, fieldpea, mungbean, and lentil ranging from 8.76 to 22.38% (wet basis) were considered in this study. Static and kinetic coefficients of friction of these pulses were determined over smooth concrete surface, galvanized iron sheet, plywood, and glass sheet. They were varied from materials to materials and depended on the roughness and wetness of the grain. The highest coefficient of friction of static and kinetic was found over concrete surface and lowest for glass sheet among the materials tested. The highest value of coefficient of friction of static and kinetic has been found for chickpea, which indicates its rough surface than those of other, six. The static coefficient of friction irrespective of grain and surface types was always greater than the kinetic coefficient of friction.