ABSTRACT
Although known for many decades, sound-and ultrasound-assisted drying has recently found renewed interest mostly because of the signifi cant progress in nonthermal dewatering (Mujumdar, 1991; Muralidhara and Lockhart, 1988). Sound is a special form of energy transmitted through pressure fl uctuations in air, water, or other elastic media. Any displacement of a particle of this elastic medium from its mean position results in an instantaneous increase in pressure. When leveling, this pressure peak not only restores the particle to its original position but also passes on the disturbance to the next particle. The cycles of pressure increase (compression) and decrease (rarefaction) propagate through the medium as a sound wave.
