Re. Vega et al., Dimensionless correlation for the heat transfer coefficient in a batch-indirect rotary drier, DRY TECHNOL, 18(10), 2000, pp. 2351-2367
A batch-indirect rotary drier heated with steam was experimentally operated
to obtain data of moisture content and temperature versus time for soy mea
l and fish meal. Operation conditions were as follow: steam pressure (1 to
4 bar), rotation speed (3.7 to 11.6 r.p.m.) and rate of vapor extraction (0
.059 to 0.256 m/s).
From experimental data the effective heat transfer coefficient between the
hot surface and the bed of solids was determined. These data were correlate
d by means of dimensional analysis as a function of the drying process vari
ables. The equation obtained for the effective Nusselt number predicts adeq
uately the effective heat transfer coefficient, for both substrates, in the
range of the operating variables studied.