The Effect of Temperature and Moisture on the Thermal Properties of Rapeseed

ABSTRACT THERMAL conductivity, thermal diffusivity and bulk density of rapeseed were measured at tem-peratures ranging from -26 °C to +19 °C and moisture contents ranging from 1 to 20 percent wet basis. The line heat source method was used to determine thermal conductivity and diffusivity. Specific heats were calcu-lated from the measured thermal conductivity, diffusivity, and bulk density. The thermal diffusivity and specific heat were found to be roughly the same as for other grains. However, the thermal conductivity is appre-ciably lower than for other grains, probably due to the spherical shape of the seeds. Increases in moisture content produce increases in thermal conductivity and specific heat except that low temperatures combined with high moisture contents apparently produce ice crystals, which causes a sharp drop in the values.