粉体工学研究会誌
Online ISSN : 1883-8766
ISSN-L : 0034-5156
13 巻, 6 号
選択された号の論文の5件中1~5を表示しています
  • 丹野 浩一, 菊田 貞雄, 高橋 藤雄
    1976 年 13 巻 6 号 p. 299-306
    発行日: 1976/06/01
    公開日: 2010/08/10
    ジャーナル フリー
    Using a model of the cylindrical vessel, the authors measured the lateral dynamic pressures at nine different heights.
    We showed in these works that the dynamic pressures which occurred durring discharge through the orifice are much greater than those of initial static conditions.
    The present report mentions about the maximum wall pressure measurements and the fundemental flow-patterns, and obtained the following results.
    (1) The characteristic wave of the dynamic pressures is classified into four large groups.
    (2) As soon as discharging cu-powder, the maximum impact pressures occurred at each measuring positions heigher than the 40mm from the orifice plate.
    (3) When cu-powder in a vessel is discharging, the internal flow accompanies by the micro bridging which is repeated by 1/500-1/600sec and the macro bridging which is repeated by 1/50sec.
    (4) On the wall pressure distribution, the large pressure value was observed near the measuring position of 30mm and 150mm.
    (5) In the case of 4mmφ of different orificies, 2mmφ, 3mmφ, 4mmφ, 5mmφ, 6mmφ, the wall pressure was minimum, when the 34mmφ vessel was used.
    (6) In the case of the 34mmφ of different vessel, 17mmφ, 24mmφ, 34mmφ, 60mmφ, the wall pressure was maximum, when the 3mmφ orifice was used.
  • 広末 英晴, 深町 敬輔, 山口 峰治, 篠原 久
    1976 年 13 巻 6 号 p. 307-314
    発行日: 1976/06/01
    公開日: 2010/08/10
    ジャーナル フリー
    It is found that the residence time of particles flowing through rotary dryers and coolers under the conditions of no air flow and air flow can be expressed by the logarithmic normal distribution, and also that the median of residence time is approximately equal to the apparent mean residence time.
    As the empirical equation for the latter had been obtained by the authors, the empirical equations concerning the geometric standard deviation, which is the other parameter in the distribution function, are studied in this paper. As a result, Eq. (8) and Eq. (10), respectively, are obtained as the empirical equations of the geometric standard deviation under no air flow and air flow. These equations approximately correlate the experimental results within the accuracy of ±20%. It is also found from the both equations that the geometric standard deviation under air flow is large in comparison with that under no air flow.
  • 宇敷 建一, 井伊谷 鋼一
    1976 年 13 巻 6 号 p. 315-327,333
    発行日: 1976/06/01
    公開日: 2010/08/10
    ジャーナル フリー
  • 倉前 正志, 吉岡 知子, 田中 達夫
    1976 年 13 巻 6 号 p. 328-333
    発行日: 1976/06/01
    公開日: 2010/08/10
    ジャーナル フリー
    The critical moisture content of drying is an essential characteristic for the design of drying equipment or the selection of optimum drying condition: nevertheless the method of predicting its value from the drying conditions and the natures of material has never been established.
    This paper dealt with the method of predicting the critical moisture content by assuming the equilibrium condition between the capillary suction pressure and the gravitational force acting on the liquid moisture in the nonhygroscopic coarse granular packed beds, and by making use of the relationship between the dimensionless capillary suction pressure and the moisture saturation, which was introduced by Kubota et al.
    As the results it was pointed out that if the condition of surface at critical point was determined, the critical moisture content was predictable from a dimensionless parameter XwgεdpL/σcosθ(1-ε)φ) depending upon the characteristics of material etc.
    Drying experiments were performed for the coarse granular materials of glass beads and calcites by varying the depth of bed, average particle diameter and initial moisture content etc. The experimental values of critical moisture content were compared with the predicted ones and the agreement proved to be satisfactory.
  • 佐納 良樹
    1976 年 13 巻 6 号 p. 339-342
    発行日: 1976/06/01
    公開日: 2010/08/10
    ジャーナル フリー
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