Effect of Ultrasonic Vibration on Fluid-to-Particle Convective Heat Transfer Coefficients

Studies were conducted to determine the potential of ultrasonic energy as a heat transfer enhancing agent in sterilization applications. Metal transducer particles were immersed in warm liquids with and without sonic agitation, and temperature histories were recorded. Convective heat transfer coefficients were calculated from the solution to the lumped convective heat transfer equation. Results indicate that fluid-to-particle heat transfer was significantly enhanced by the use of sonic energy, and that within the range of variables investigated, the amount of enhancement was dependent more on natural convection and standing wave patterns than particle size and energy input per unit mass.