Probabilistic Approach to Particle-Wall Contact Time in Fluidized Beds

The heat transfer between submerged surface and particles in fluidized bed is affected by particle migration to and from the exchanger surface. A new probabilistic model was developed for particle migration and particle-wall contact time distribution based on a classical gamma function. The existing models suggest a decrease in contact time by increasing the gas velocity. However, it has been experimentally shown that the contact time increases in turbulent regime by increasing the gas velocity. A theoretical probabilistic model was developed to represent such a trend. The model is in good agreement with the experimental data.