Experimental methods of estimating heat transfer in circulating fluidized bed boilers

Artikel i vetenskaplig tidskrift, 1992

Four different experimental methods have been used for the estimation of the bed-to-membrane wall heat transfer in a 12 MW,, circulating fluidized bed boiler. The methods are compared for a case of normal operating conditions and the measured heat transfer coefficients are presented. In the central part of the combustion chamber where most of the cooling surface is located, the cross-sectional average suspension density normally varies in the range of 10-20 kg m -’ and the heat transfer coefficient is around 130 W m ’ K-’ with a scatter of + 15% due to the different methods. The methods are critically analyzed and the heat transfer data are compared with relevant literature data.