粉体のタッピング現象について

概要

論文の詳細を見る
The reological properties of flow of powders, which are different from those of solids and liquids, exhibit very interesting phenomena.　In this paper, packing characteristics have been examined by the tapping of powder bed The results may be summarized as follows:　(1) In case of powders that particle size are larger, the following equation is established between bulk density ρ_n and tapping times n.　ρ_n = α.ln + β (1)　(2) In case that particle size is larger than some value or particle shape is arranged properly, ρ_n decreases with increase of n. Furthermore, at more tapping times the values of ρ_n are somewhat scattered, because these powders show dilatant phenomena. And in these cases equation (1) is not applicable.　(3) For foods powders, baby powder, cleanser, feldspar, quartz and Toyoura sand, the following equatton which is proposed by Taneya et al. generally exists.　γ_n = (a.b.n)/(1+b.n) (2)　Where a is infinite compressibility, b is the coefficient that represents the fluidity of powders.　(4) In foods powders, the infinite compressibility of cocoa, flour and starch are larger, that of sugar, creama white and whole milk powder are smaller.　(5) It becomes clear that Roller's equation for tapping is not applicable within the limits of this experiment.
山形大学の論文
1980-01-21