SCIENTIFIC AND TECHNICAL BASIS FOR THE DEVELOPMENT OF INSTALLATIONS WITH MICROWAVE POWER SUPPLY FOR PROCESSING RAW MATERIALS AT AGRICULTURAL ENTERPRISES

Abstract

The developed methodology of designing installations with microwave power supply for heat treatment of raw materials of agricultural enterprises is described. The scientific problem is the low energy efficiency of installations designed for heat treatment of raw materials with steam-water mixture, convective heat supply, the absence of continuous-flow installations for farms that ensure the preservation of consumer properties of the heat-treated product at reduced operating costs. (Research purpose) The research purpose is developing the scientific and technical foundations of installations with microwave power supply for processing raw materials at agricultural enterprises. (Materials and methods) Carried out three-dimensional modeling of the structural design of the installations in the Compass 20 program, determined the electrodynamic parameters of the “generator-resonator” system in the CST Microwave Studio program. (Results and discussion) Resonators of different structural designs have been developed for different types of raw materials, in which electromagnetic safety is ensured by forbidden waveguides, decelerating systems in the form of a chain of connected resonators, comb, cylindrical spiral, rod ring, counter pins. In resonators with curved surfaces, several magnetrons of the same frequency or operating at close frequencies with dissectors were used to change the frequency of the generator and increase the number of types of vibrations, and mixing, transporting mechanisms that allow maintaining the well of the technological process less than 0.5 and observing the dimensions of the raw materials in accordance with the depth of penetration of the wave. It was found that when using several magnetrons, the concentration of the electromagnetic field energy in the resonator volume and the reduction of radiation losses are achieved using ceramic reflectors. The values of the intrinsic Q-values of the resonators were determined to evaluate the thermal efficiency coefficient. (Conclusions) Using the examples of an animal colostrum defroster, instant milk pasteurizer and a three-section hop dryer with air-cooled magnetrons, the implementation of the scientific and technical fundamentals of designing microwave equipment for processing raw materials of agricultural enterprises was shown. It was revealed that they provide ways to achieve a continuous mode of operation of the equipment in compliance with electromagnetic safety without a shielding housing by implementing metal-dielectric resonators with decelerating systems and ceramic reflectors with an optimal arrangement of waveguides with air-cooled magnetrons on the curved surfaces of the resonators.