Abstract
The aim of this work is to investigate the fluid dynamic behavior of a cold bubbling fluidized bed gasifier, both from an experimental and a numerical point of view. The experimental analysis has been carried out considering three heights of bed particles and several fluidization velocities for each height. The experimental average pressure drops through the bed have been compared to theoretical values, showing a a general good agreement. Furthermore, the influence of the fluidization velocity and bed height on the fluid dynamic behavior of the gasifier has been investigated. A preliminary numerical analysis has been performed for a fixed height of the bed and a given fluidization velocity. The simulations have been carried out with a commercial software by using the Two-Fluid Euler-Euler´s Model (TFM) closed with the Kinetic Theory of Granular Flow (KTGF). To validate the numerical models used to perform the simulations, a first comparison has been made between the numerical and the experimental average pressure drop. Furthermore, the fast Fourier transform (FFT) analysis of the numerical and experimental pressure fluctuations have been compared in order to provide a deep insight on the bubbles’ behavior.