Summary
In order to develop an ultra-sonic drying system for agricultural products, an ultra-sonic drying device with ultra-sonic generation plate, 19.5 KHz, was designed and its performance was investigated. This paper focuses on the absorption characteristic of ultr~hsonic wave into the layer of rough rice during drying period. Ultrasonic absorption properties of rough rice were measured at sound pressure level between 141.1 and 158.3dB, and layer thickness from 0 to 120 mm. The sound pressure level decreases exponentially with traveling length and its energy was translated to heat energy in the rough rice layer.HomePageKeywords: ultra-sonic drying, rough rice, absorption, energy balance