Mr. Golriz, SUSPENSION-TO-WALL HEAT-TRANSFER IN A 12-MW(TH) CIRCULATING FLUIDIZED-BED COMBUSTOR, International journal of energy research, 20(7), 1996, pp. 569-579
An experimental investigation was carried out to study the effects of
operating parameters on the local suspension-to-wall heat transfer in
the combustor of a 12-MW(th) circulating fluidized-bed (CFB) boiler. T
he heat transfer coefficients were measured with a conduction-type hea
t flux meter at five different vertical levels. The measurements cover
ed a range of superficial gas velocities from 4 to 6 m/s, a bulk bed t
emperature from 800 to 850 degrees C and a suspension density from 6 t
o 70 kg/m(3) for 270-mu m silica sand particles. The heat transfer coe
fficient for the membrane wall in the combustion chamber of the CFB bo
iler was in the range of 100 to 180 W/m(2) K for the range of operatin
g conditions employed in this work. The beat transfer coefficient decr
eased with increasing height and increased with increasing bulk bed te
mperature, superficial gas velocity and suspension density. Based on t
he experimental data, a simple correlation is proposed for predicting
the suspension-to-membrane wall heat transfer coefficient. The results
were analysed and compared with the experimental data of other worker
s.