Table 2 listed the experimental parameters and their values. The gas
flow rate was measured and adjusted by a rotor flowmeter. A manometer
was installed to record the pressure signals above the distributor.
Acoustic field systemmeasurementswere performedwith signal generator,
sound amplifier and loudspeaker. The electric signal was then
amplified with a sound amplifier and sent to a loudspeaker installed
on the top of the fluidized bed. A precision sound pressure level meter
was used to measure the sound pressure level in the fluidized bed,
with a 160 dB maximum sound pressure level to be measured. The
sound frequency was controlled by a signal generator.
The moisture content values and the drying rate values were
calculated through the following equations: