Machinery & Energetics (Aug 2023)
The screw-type electrothermomechanical converter as a source of multiphysical influence on the technological environment
Abstract
In ensuring the reliability of electromechanical converters in harsh conditions, the problem of increasing the energy efficiency of their application through structural, functional, and thermal integration with the technological environment is present. Thus, the research aims to determine the conditions of the direct multiphysical impact of a screw-type electromechanical converter on the technological environment. The method used is based on determining the list of features of screw-type electromechanical converters using the Comsol Multiphysics software, and a combination of three-dimensional and two-dimensional finite element models limited to the rotor with the inclusion of blades in the computational domain. Two variants of forming an algorithm for the multiphysical impact on the technological environment were studied: local concentration of the impact in certain areas of the rotor and uniform distribution along the rotor surface of temperature, pressure, magnetic induction, and electric field strength. The regularities of the distribution of magnetic induction on the outer surface of the ferromagnetic rotor at different azimuthal locations of the frontal parts of adjacent stators have been established. The distribution of the normal component of the magnetic flux density at the contact with the process medium in the form of rutile product or ilmenite concentrate is determined. The consumed electric energy is distributed in the stator tooth zone and the zone of electromagnetic field penetration into the rotor. Eddy currents are concentrated at the penetration depth from the rotor’s inner surface, with the penetration depth depending on the thermal state and sliding mode. The electric field intensity on the rotor’s outer surface reaches 0.8 V/m in the areas opposite the stator crowns and depends on the current activity of the phases at a given moment. Controlling the thermal and speed regime of the rotor can be used to create conditions for bioenergy stimulation on its surface in places of contact with the medium or to support the process of electrode heating of the technological medium. The adequacy of the mathematical models proposed for numerical modelling to the experimental data of the prototype of the screw electromechanical converter was confirmed, with deviations not exceeding 9.5%. The obtained results can be used to predict the optimal indicators of electromagnetic and heat transfer processes in screw electromechanical converters associated with the technological environment
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