Cfd Modelling of the Acoustic Streaming Induced by an Ultrasonic Horn Reactor

Power ultrasonic reactors have gained a lot of interest in the food industry given the effects that can arise from sound induced cavitation. However, most of the new food processing developments have been based on empirical approaches. Thus, there is a need for mathematical models which help to understand, optimise and scale up ultrasonic reactors. In this work, a CFD model has been developed, to predict the acoustic streaming induced by an ultrasonic horn reactor. In the model it is assumed that the horn tip is a fluid inlet, where a turbulent jet flow is injected into the vessel. The hydrodynamic momentum rate of the incoming jet is assumed to be equal to the total acoustic momentum rate emitted by the acoustic power source. CFD predictions show excellent agreement with the experimental data at all studied power densities. This model successfully describes hydrodynamic fields (streaming) generated by ultrasound fields.