Experimental work was conducted to study the influence of
bulk bed dispersity on contact heat transfer. The contact heat
transfer between the inner drum wall to the covered surface of
the solid bed was experimentally investigated in an indirectly
heated rotary drum with a diameter of D = 0.6 m and a length of
L = 0.45 m. The temperature of the inner drum wall and the solid
bed were measured by K-type thermocouples assembled on a
rod, upon which these thermocouples were specifically arranged
at different radial distances from the inner wall. Experiments
have been carried out with glass beads as the test material, with
systems defined as monodisperse, bidisperse and polydisperse
and with different particle size ratios. The operating parameters,
rotational speed and filling degree are varied in the range of 1 to
6 rpm and 10 to 20% respectively. The measured contact heat
transfer coefficients for all disperse systems were compared with
four model approaches from the literature in terms of R2 values.
Good agreement between the experimental measurements and
the two model approaches were achieved.
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.