HEAT TRANSFER IN VIBRO-FLUID1ZED BED

EFFECT OF PULSATED GAS FLOW

Abstract

Heat transfer coefficient between fluidized bed and a small heater in vibro-fluidized bed was investigated experimentally, and the coefficient in the vibrated bed was found to be larger than that in an unvibrated bed. Measurement of pressure fluctuation indicated that mechanical vibration with larger vibratory acceleration than the gravitational caused pulsated gas flow through the bed.
Considering a simple piston model for the motion of the bed, an equation is derived to describe the pulsated gas flow.
The heat transfer coefficient is correlated with gas velocity, taking account of the pulsating gas velocity estimated from the equation and the experimental results of pressure fluctuation. The coefficient in a vibro-fluidized bed is found to agree well with that in a bed without vibration, except for the range of larger gas velocity with smaller particles.