This paper presents the heat transfer model for the gasifier to predict the temperature profile in the bed using the single zone sub-model. The single zone sub-model is also used to verify the correctness and to demonstrate the effect of various parameters for e.g. solid/fluid flow, temperatures of inflow/outflow control volume (CV), heat generation/absorption and with/without heat loss. The study shows that solid/fluid flow, inflow CV temperature and heat generation/absorption within the CV of interest are the strong influencing parameters, whether, the outflow CV temperature has insignificant effect on the temperature values of the CV of interest. The six similar zones correspond to preheating, drying, pyrolysis, oxidation, reduction and annular jacket zone are also coupled in order to predict the temperature profile in the gasifier bed. The simulation result shows that temperature of the down stream zones are more sensitive to heat generation in the bed as compared to upstream zone temperature, while the increase in gas flow rate resulting into the decrease in temperature profile depending upon the values of heat generation/absorption in bed is being fixed.

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