Modelling of solid fuel stoves

Abstract

This work presents a detailed theoretical study of solid fuel combustion in a domestic stove (make Harsha, RRL, Bhubaneswar, India). In this work different steady state as well as unsteady state combustion models have been formulated, which include the description of all the chemical and physical processes taking place during the solid fuel combustion inside the stove. Steady state models involve the calculation of effective maximum flame temperature, suction of combustion air created by hot flue gases inside the stove and the propagation of ignition front inside the stove. Unsteady state mathematical model involves all the processes occurring simultaneously or sequentially during the solid fuel combustion such as moisture evaporation, devolatilization, pyrolysis and homogeneous and heterogeneous combustion reactions. This unsteady state model gives the temperature profiles at different locations inside the stove and fuel mass loss (combustion) rate, which can be further used to calculate the power delivery by the stove during combustion. The model shows good agreement with the experimental results. These models can be used to find the effect of stove geometry and fuel properties on the stove performance parameters such as effective maximum flame temperature, suction created inside the stove, propagation of ignition front inside the stove, and fuel burn rate, which play an important role in the design of such stoves for maximum thermal efficiencies.