An acoustic method of studying sequential explosions during gas combustionin bubbling fluidized beds

Dynamic phenomena associated with the combustion of gaseous mixtures of a f uel and air in a bubbling fluidized bed have been analyzed. The multiphase hydrodynamic structure of a bubbling fluidized bed leads to combustion whic h can be either explosive in the bubbles or continuous in the emulsion phas e. These two modes of combustion can be distinguished by analyzing the acou stic effects. An algorithm is proposed to determine the frequency of the ex plosions. This algorithm has been used to examine experimental results obta ined in laboratory-scale experiments. It is shown that the frequency of the explosions decreases with rising temperature. This leads to continuous com bustion above a certain "transition temperature." (C) 2001 by The Combustio n Institute.