MODELING AND SIMULATION OF COMBUSTION OF WOOD

Abstract

In this dissertation work modeling of wood combustion has been done by two different reaction schemes. Importances of renewable energy, their future aspects are also explained. Some of the progress that, owing to modeling and numerical simulation, has been made to the understanding of chemical and physical processes, which occur during combustion of solid wood, is presented. The first part of the dissertation deals with theoretical analysis of combustion and pyrolysis process. Then after, application and uses of products are presented. Thermal degradation processes of charring wood and, in general, cellulosic materials are done to get volatile gases and char. Solid fuel degradation has been described by kinetic models of different complexity, varying from a simple one- step global reaction, to multi-step reaction mechanisms. In first reaction scheme, wood first decomposes into volatile and gases, then products itself reacts to give final volatile and gas. In second reaction scheme, wood first decomposes into volatile, char and tar after that tar further decomposes into volatile gas and char. MATLAB toolbox is used to simulate ordinary differential equations. Effect of temperature and order is analysed to get better yield of volatiles. The study provides a fundamental modeling approach that will enhance understanding of the effects of physical properties and processes on the chemistry of devolatilizing biomass. At higher temperatures the performance of the reactor is identical for all sets of order of reaction that are taken. The optimum temperature is found out as 850 K as there is no change in time of 100% pyrolysis of both sets of order. of reactions.