Sensitivity Analysis of a Fixed Bed Combustion Model
Artikel i vetenskaplig tidskrift, 2007
The ability to model the combustion of biofuels in a fixed bed is evaluated by a sensitivity analysis. The
analysis treats the uncertainty of model parameters related to heat transport, reaction rates, and composition of
volatiles. The scatter of the parameters is estimated from the differences between several published correlations.
The results are compared with measurement data and possible model simplifications are discussed. It is shown
that the bed model is able to reproduce the ignition rate and the maximum temperature. Prediction of these
properties is relatively insensitive to the uncertainty of most of the parameters. Gas concentrations within the
bed are more difficult to predict. They are greatly influenced by the composition of the volatile gas released
during devolatilization. Also the composition of the volatile gas has a significant influence on the ignition of
the gas in the model, affecting the ignition rate, particularly at low airflows. Moreover, the investigation shows
that treatment of radiation can be simplified, and the number of gas species included in the model can be
restricted without significant losses of model generality.