SIMULATION MODELING OF MILK HEATING BY THE ENERGY OF MICROWAVE FIELD
Heat treatment of dielectric materials and food products is one of the important directions in the development of the production of various products. The use of the electromagnetic field energy of ultrahigh frequencies for drying, heating, defrosting and pasteurizing food products is promising, since such technologies are suitable for processing various dielectric materials and, at the same time, are efficient and environmentally friendly. Despite many developments in the field of microwave processing of materials, the creation of a universal device suitable for heat treatment of any kind of materials is difficult because of the variety of their shapes and sizes, as well as the significant difference in the electrical properties of variouse dielectrics. Therefore, in each specific case, it is required to create an optimal design of the device and choose the option for exciting the electromagnetic field. This work is devoted to modeling the absorption of energy of the microwave electromagnetic field in a device for milk pasteurization. Using CAD FEKO, a 3D model of the device was built and its operation was modeled. The study of the influence of the angle of inclination of quartz tubes on the distribution of the electromagnetic field in the waveguide is carried out. The results show that most of the power is absorbed closer to the beginning of the waveguide, and this phenomenon is more pronounced with an increase in the angle of inclination of the tubes. On the basis of performed calculations, the optimal angle of inclination of the tubes was determined. The influence of the diameter and material of the tubes was also considered. The distributions of the electric field and specific power absorbed per kg of dielectric in the waveguide are obtained. The accuracy of the results is evaluated. Possible modifications of the proposed design of the pasteurization device can be made by choosing other variants of the arrangement of the tubes with milk. The thickness of the tube's walls can also affect the absorbed power. In addition, the composition of milk can change its electrophysical properties, and therefore can also affect the level of absorbed power. However, these questions require further research.