Papers by Author: Liu Yong Yang

Abstract: The thermal conductivity of green teas has been used as engineering parameter in the design of processes and machines for drying, storing and aeration. The thermal conductivity of green teas was determined and its changes with moisture content, bulk density investigated. The thermal conductivity values of green teas increased from 0.036 to 0.438 W m^–1 K^–1 and from 0.041 to 0.568 W m^–1 K–1 for low and high (loose and dense) bulk densities, respectively, as the moist^{Superscript text}ure content increased from 5.3 to 78.7% dry basis. The change of the thermal conductivity of green teas with temperatures at different bulk densities shows that it increased from 0.035 to 0.045 and 0.042 to 0.053 W m^–1 K^–1, respectively, as the temperatures and bulk density increased. The thermal conductivity values obtained with the high bulk density was higher than those obtained with the low bulk density for green teas.

Abstract: The thermal diffusivity of green teas has been used as engineering parameter in the design of processes and machines for drying, storing and aeration. The thermal diffusivity of green teas was determined and its changes with moisture content, bulk density investigated. The thermal diffusivity values of green teas decreased from 8.126×10^-8 at 250 kgm^-3 to 5.037×10^-8 m²s^–1 at 550 kgm^-3. The change of the thermal diffusivity of green teas at different moisture content shows that it increased from 8.281×10^-8 at 5.3% db to 12.617×10^-8 m²s^–1 at 70.0% db and from 7.497×10^-8 at 5.3% db to 12.464×10^-8 m²s^–1 at 70.0% db, respectively, as bulk density increased.