Sei-ichi Oshita

Drying Characteristics of Gelatinous Materials Irradiated by Infrared Radiation

ABSTRACT As a food model for infrared drying, a gelatinous bed composed with agar-gel and powder was used. To study the influences of the bed conditions, the emissivity of the powder materials and their initial-volume fractions were considered. To study the influence of the radiative heat source, the spectral distribution of irradiation power was examined. We selected three kinds and several initial-volume fractions of powders (alumina, silver and stainless steel) and used two types of infrared heaters (a far-infrared heater and a near-infrared heater). Infrared drying of the gelatinous bed was performed, and a heat transfer model for infrared drying of the gelatinous bed was constructed. The model-calculation results were compared with the experimental results, and agreed with the experimental results consistently for FIR drying and qualitatively for NIR drying. The present study shows a fundamental guideline on the application of infrared radiation to the drying operation.

Bulk Thermal Diffusivity Measurement of Grain Rice by New Fast Method

The fast method of measuring thermal diffusivity was proposed. It is based on the newly developed technique to estimate temperature distribution of the material at desired time without the knowledge of initial temperature distribution.