Bulk Thermal Conductivity and Diffusivity of Barley

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Res. Bult., No. (53), PP., (5-17) 1995 Bulk
Thermal Conductivity and Diffusivity of Barley
Ali I. Hobani Mohamed H. Tolba Agricultural
Engineering Department, College of
Agriculture, King Saud University, P.O. Box 2460,
Riyadh 11451, Saudi Arabia. Abstract The
bulk thermal conductivity and diffusivity of two
varieties (Justo and Sahrawy) and one line of
barley (CR279) were experimentally determined.
The thermal conduc vity was found to linearly
increase with the increase in moisture content in
the range of 10 to 30 (w.b.). The values of
bulk thermal conduc vity ranged from 245 to 288,
from 193 to 239, and from 210 to 285 (mW/m.ûC)
for the Justo, Sahrawy and CR279, respec vely.
The bulk thermal diffusivity, on the other
hand, was found to linearly decrease as the
moisture content increased from 10 to 30
(w.b.). The values of thermal diffusivity changed
from 7.01 x l0-4to 6.03 x l0-4, from 8.30 x
l0-4to 7.84xl0-4, and from 8.76 x l0-4 to
8.18 x l0-4 (ms/h) for the Justo, Sahrawy and
CR279, respec vely. The bulk densi es were
also determined and used to calculate specific
heat of barley grains. The average values' of
the specific heat were 2.056, 1.542 and 1.596
(kJ/kg.ûC) for the Justo, Sahrawy and CR279,
respec vely. This work was funded by the
Agricultural Research Center, College of
Agriculture, King Saud University.