Background. Predictive models in simplified mathematical formulation, describing only the burnup process of coke particles residue, are an effective tool for studying and improving technologies of pulverized coal burning in power boilers. To use such models, it is necessary to set the time of fuel particles coke residue burnup, which is, in fact, the difference between the average time of particles residence in the furnace and the ignition delay time. Currently, there are no solutions to the problems related to this value definition in specific conditions. This article is dedicated to determining of fuel particles ignition delay time and using these data for adaptation of the mathematical model.
Materials and methods. We have earlier conducted a verification procedure for the mathematical model used in this work and determined its parametric sensitivity.
Results. We have developed a method of determining the particle ignition delay time. Its novelty consists in its ability to analyse the dependence of mechanical underburning on the burnup time (this dependence can be obtained by applying the mathematical model of polyfraction fuel burnup) and to determine the burnup time corresponding to mechanical underburning obtained under specific conditions. Ignition delay time is determined as the difference between the average time of particles residence in the furnace and the obtained burnup time. For the conditions of one of Donbass power plants using TP-109 boilers we have established that the ignition delay time before the burner reconstruction was 0,9–1,2 s, and after these burners were replaced with bladed-jet ones with improved twist parameters it was 0,41–0,51 s.
Conclusions. The proposed method of determining ignition delay time and the results obtained with its help can be used to adjust the simplified mathematical model of pulverized coal burning to specific conditions, for example, in the case of buying new equipment or reconstructing the old set.