Masaru Hattori

Flow Patterns of Ice/Water Slurry in Horizontal Pipes

The authors have observed flow patterns of ice/water slurry flow through horizontal circular pipes, and measured pressure loss for small diameter pipes, using three classes of ice particles. The slurry flows are classified into three patterns, dispersed-particle flow, cluster flow, and column flow. They are presented on a plane of two dimensionless parameters, the ice fraction f and the ratio of mixing energy to cohesion energy, π mix . The pressure loss for small diameter pipes is estimated accurately by the formula proposed in previous studies by the present authors based on experimental data for larger pipes.

Water Infiltration and Heat Transfer in One Dimensional Unsaturated Packed Beds.

Water and heat transport in unsaturated packed beds due to supplying hot water have been investigated experimentally and theoretically. Using various sizes of glass beads, capillary pressure and permeability in packed beds were measured in unsaturated beds. The distributions in water saturation and temperature were predicted for one dimensional packed bed, based on a model assuming local thermal equilibrium among water, gas and particles at any specific space. The predicted temperature distributions were compared with the experimental results obtained using various glass sizes. In layered packed beds, water saturation becomes discontinuous at the interface of two layers because of the difference of the water characteristics between two beds. Water penetrates faster in coarse-over fine-textured profile compared with in fine-over coarse-textured profile. Similarly, the temperature rises faster in former profile under the same supplied heat quantity.

Liquid holdup and liquid-to-particle mass transfer for gas continuous two phase flow in packed beds.

The purposes of this report are to establish the measuring systems for liquid holdup and to obtain the relationship between the flow and the mass-transfer coefficients for gas continuous two-phase flow in packed beds. Liquid holdup existing in packed beds was obtained by using the method of neutron attenuation ad a correlation for liquid holdup was presented as a function of the Reynolds number and the Galilei number. Liquid-to-particle mass-transfer coefficients for gas continuous two-phase flow depended on the liquid holdup, and the modified correlation for mass-transfer coefficients was obtained by modifying the Reynolds number and the Sherwood number, considering the actual liquid velocity in packed beds and the ratio of the mass-transfer area to the sectional area of flow.