2018 年 55 巻 11 号 p. 588-593
Wet granules are applied for various fields due to their high workability and cost performance. However, it is difficult to observe the water distribution of wet granules directly because of the extremely small amount of water. In this study, the water distribution of wet granules was investigated by confocal laser microscope and quantitatively analyzed by using autocorrelation function. Furthermore, the correlation length of wet granules estimated from autocorrelation function was compared with their shear properties. Consequently, it was elucidated that angle of internal friction of wet granules decreased with increasing water volume between particles. These results indicated that water of wet granules works as drag reduction agent under shear conditions.