Guest speaker: Motion of fuel particles immersed in bubbling fluidised beds
Antonio Soria-Verdugo (Carlos III University of Madrid)
Room 1.69, Queen's School of Engineering, University Walk
As part of the Autumn term seminar series, the Fluid & Aerodynamics Research Group invite guest speaker Antonio Soria-Verdugo from the Department of Thermal Engineering and Fluid Mechanics at Carlos III University of Madrid to give a seminar.
Title:"Motion of fuel particles immersed in bubbling fluidised beds".
Fluidised beds are employed in industry because of their excellent properties involving heat and mass transfer, and their capability to establish and promote chemical reactions inside them. A variety of processes can occur inside a fluidised bed, including drying, heat exchange, thermal conversion of solid fuels, and coating of particles. Most of the applications of fluidised beds involve the motion of objects inside the bed. Fuel particles, catalysts, and agglomerates are examples of typical objects found inside a fluidised bed. It is necessary to characterize the motion of these objects, principally the motion of fuel particles, within the bed to establish the region of proper performance and to prevent operational problems such as the existence of hot or cold spots in a reactor or the appearance of de-fluidised zones due to the existence of agglomerates.
The main characteristics of the fuel particles motion were studied in a pseudo-2D bed. By direct visualizations of the fuel particle trajectory, applying Digital Image Analysis (DIA), the preferential paths and the principal parameters that affect the motion were established. Statistical values for these parameters were obtained experimentally for different operating conditions of the fluidized bed, i.e. fluidizing air velocity and bed height. These statistical values were employed for semi-empirical models based on Monte Carlo simulations of the motion of fuel particles in pseudo-2D bed. The estimations of the semi-empirical model were compared to experimental measurements in pseudo-2D beds and lab-scale 3D beds, obtaining a good agreement.