HIGH FREQUENCY ELECTROMAGNETISM, HEAT TRANSFER AND FLUID FLOW COUPLING IN ANSYS MULTIPHYSICS
Cristina M. Sabliov, Deepti A. Salvi and Dorin Boldor
Biological and Agricultural Engineering Department,
Louisiana State University Agricultural Center, Baton Rouge, LA, USA
ABSTRACT
The goal of this study was to numerically predict the temperature of a liquid product heated in a continuous-flow focused microwave system by coupling high-frequency electromagnetism, heat transfer and fluid flow in ANSYS Multiphysics. The developed model was used to determine the temperature change in water processed in a 915 MHz microwave unit under steady-state conditions. The influence of the flow rates on the temperature distribution in the liquid was assessed. Results showed that the average temperature of water increased from 25°C to 34°C at 2 l/min and to 42°C at 1 l/min. The highest temperature regions were found in the liquid near the center of the tube, followed by progressively lower temperature regions as the radial distance from the center increased and finally followed by a slightly higher temperature region near the tube’s wall corresponding to the energy density distribution given by Mathieu function. The energy distribution resulted in a similar temperature pattern, with highest temperatures close to the center of the tube and lower at the walls. The present study showed that coupling the models of three physical phenomena (heat transfer, fluid flow and electromagnetism) was possible in ANSYS Multiphysics. The model can be improved to account for complex boundary conditions, phase change, temperature dependent properties and non-Newtonian flows, which make the objective of future studies.