Research On Double Flywheel Aluminum Billets Heating Device Based On Electromagnetic Induction Theory

With the wide application of extruded aluminum alloy and the establishment of an environment-friendly society,the preheating of aluminum alloy materials for more energy saving and environmental protection has been continuously studied in the industry.By electromagnetic induction heating can convert electrical energy to electromagnetic induction phenomenon,is a kind of environmentally friendly heating method,but in the aluminum alloy heating the smaller resistivity and magnetic permeability of ferromagnetic materials,due to the heat generated by the induction coil significantly increased,leading to low heating efficiency.Therefore,dc induction heating technology came into being.This article is set in a dc induction heating device,and the equivalent magnetic circuit modeling,finite element coupling mathematical modeling of magnetic field and temperature field,influence analysis of parameters on induction heating,and thermal efficiency analysis are carried out.The main work contents are as follows:Firstly,the overall design of the permanent magnet induction heating device is completed according to the principle of DC induction heating,and the equivalent magnetic circuit model of the permanent magnet induction heating device is established.Then the heating principle and the equivalent magnetic circuit model are used to determine the influence of the heating effect of the device.parameter.Then,according to Maxwell's equation,the governing equation of the internal eddy current field of the aluminum rod is derived.The COMSOL software is selected as the simulation tool.The separation method is used to analyze the magnetic field and temperature field.Secondly,the magnetic field and temperature field models of permanent magnet induction heating device are established by using finite element software.The magnetic induction intensity distribution,eddy current distribution,eddy current output power and internal temperature field distribution of aluminum rod are simulated and analyzed.The finite element simulation results show that the larger the outer diameter of the permanent magnet,the larger the output power of the eddy current;the thickness of the permanent magnet has a critical value on the output power of the eddy current.When the thickness is less than 50 mm,the larger the thickness,the larger the output power of the eddy current;The smaller the flywheel speed is,the higher the output power of the eddy current is.The influence of the number of permanent magnets on the output power of the eddy current is more complicated.However,when the number of poles is four poles,the output power of the eddy current is the largest;the reciprocating speed of the aluminum rod determines the aluminum rod.The axial temperature distribution gradient,the slower the speed,the greater the axial temperature gradient.Then,through the surface fitting method,the relationship between the eddy current output power and the moving speed of the aluminum rod on the temperature difference between the two ends of the aluminum rod is established.The results show that the larger the output power of the eddy current,the faster the moving speed of the aluminum rod,the axial direction of the aluminum rod.The greater the temperature difference between the ends.Through the analysis and comparison of different parameters,the optimal parameters of a set of permanent magnet induction heating devices are obtained.Under this parameter,the heating power is maximum and a good temperature gradient can be formed.Then,through calculation,the synchronous motor and the servo motor required by the induction heating device satisfying the optimal parameters are specifically satisfied,and the total energy efficiency of the induction heating device can be calculated to be more than 78% under the parameter.Finally,the simulated values are compared with the experimental values to verify the accuracy of the finite element modeling,and it is proved that the permanent magnet induction heating device can heat the aluminum rod to the extrusion temperature within five minutes.