Sedimentation velocity -U_d+u_mj and expansion ratio of emulsion phase (L_e-L_c)/L_c of FCC particles, alumina particles, glass beads and polyvinylchloride particles were measured in 6.6cm insidediameter fluidized bed. The results obtained are as follows: The sedimentation velocity is nearly equal to superficial gas velocity flowing in emulsion phase and depends on the properties of solid particles. That is, in the case of solid particles with large mean particle diameter, the sedimentation velocity is equal to superficial minimum fluidizing gas velocity umf. However, it becomes gradually higher than umf and expansion ratio of emulsion phase larger, with decrease of the mean particle diameter and increase of the size distribution. For the range where the sedimentation velocity and the expansion ratio of emulsion phase are independent of gas velocity respectively, the following empirical equation is obtained.
[(-U_d+u_j)/u_m-1]=34[(L_e-L_c)/L_c]²

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A numerical analysis has been performed to determine the flow development and the heat transfer characteristics for laminar natural convection between two fully submerged, heated vertical parallel plates with unequal uniform wall temperatures.
Numerical results are presented for the variations of velocity, temperature, induced flow rate, and local and mean Nusselt numbers for fluids having Prandtl number 0.7 and 10.
For the plates with equal wall temperatures, the numerical results are compared with the experimental results hitherto reported.

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The shear stresses and the mass transfer coefficients at the wall of liquid fluidized bed were measured electrochemically. Based on a two-region model newly proposed for the flow behavior in particulate fluidized bed, it is demonstrated that friction factors are correlated with only one variable γ and also S_t with γ and S_c. These relationships were verified experimentally over wide ranges of particle size and fluid velocity. The dimensionless variable γ is the product of Re_m, Fr_m, and density ratio. Among them the effect of Fr_m, has been overlooked in the previous investigations. Eddy diffusivity was applied to both momentum and mass transfer process, and the estimated values of mass transfer coefficients were in fair agreement with experimental results.

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The mass transfer of three different organic acids in the di-n-butylphthalate-water system was observed in two dimensional test cell. The masstransfer rate through the interface accompanied by interfacial turbulence was measured by the concentration profile of these acids near the interface obtained by Mach-Lender interferometric method. These three acids were transferred perpendicular to the gravitational axis so that Rayleigh effect due to the density change of solution might be neglected.
Mass flux accompanied by interfacial turbulence is strongly affected by the wave length of interfacial turbulence under the same driving force and time after making interface. The mass flux with 0.54-2.4 cm wave length was 2-4 times larger than that calculated by the penetration theory. An empirical equation of mass transfer coefficient was obtained.

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The change of temperature profile within the spherical samples of magnesium hydroxide during drying and decomposition in a fluidized bed was recorded, continuously and analysed. The samples were prepared by hydrating the mixture of activated MgO powder, quartz powder and water.
The effective diffusivities of the sample spheres during the drying process were obtained by the nonisothermal analysis applying the reaction diagram of Ishida and Shirai. They quite well agreed with those calculated theoretically based upon the pore size distribution and gas permeability measurements.
The thermal decomposition was performed under high temperature region where the pressure within the spherical sample becomes much higher than the atmospheric pressure. The pressure at the reaction surface estimated by the non-isothermal analysis appeared much lower than the equilibrium pressure, indicating that the chemical reaction resistance plays an important role in the rate of this reaction.

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The axial mixing phenomena in a turbulent pipe flow is described by the one dimensional dispersion model in the transient domain, which is frequently used in turbulent field theory. In this case, the formula which expresses the dispersion of time or space can be related to the friction factor, the mean velocity, the pipe length and the characteristic length. To confirm this relation, experiments by means of the pulse testing method were made by using smooth pipes of different length and diameter. The experimental results satisfy approximately with the relation. And the characteristic length, which is important factor describing the scale of the transient domain, is proportional to the pipe diameter only. Besides, the parameter of mixing, such as the dispersion coefficient or the Peclet number, is examined from view points of application.

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Considering the contribution of both coalescence and break-up, the behavior of liquid droplets in an agitated vessel was investigated experimentally. The initial rate of change in total number of droplets was obtained at a sudden change of the agitating speed. From the experimental results, using the method offered here to separate the coalescence and break-up rates, the parameters in the dynamic balance equation of total number of droplets were determined. The equation can be expressed finally by the form
The coalescence term (the second term of the right side) agrees well to reported results. And from the analysis of the break-up term, it is found that the break-up of droplets is caused by turbulence and takes place predominantly in the vicinity of the impeller tips.

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