Research On Fixation Machine With Electromagnetic

Fixation is the important step of Green Tea early fabrication which affects the quality of tea.The cylinder fixation machine is the most widely used tea fixation machine on the market.Due to the way of heating by using gas and resistance,the utilization of energy is low which is not conducive to energy-saving,and the quality of tea is not good because of the slow temperature response.Therefore,it is necessary to design an efficient fixation machine which can reduce the energy consumption and improve the quality of tea by the high speed of temperature response,Electromagnetic heating technology is widely used in industrial production which has the characteristics of fast heating speed,high efficiency and precise temperature control.The fixation machine with electromagnetic is still in the initial stage,the high cost based on experiments.Therefore,numerical simulation technology has great significance for the design and research of such systems.Based on the electromagnetism and heat transfer,to simulate the heating process by the analysis method of ANSYS software coupling field,temperature field of roller heating process,and analyze the key factors affecting the efficiency of heating,put forward the design scheme of key technologies for fixation machine with electromagnetic.The main work and achievements of this paper are as follows:(1)Based on the theory of electromagnetic field and the theory of heat transfer,the theoretical formulas of electromagnetic field and temperature field distribution of electromagnetic induction heating drum were deduced and the mathematic analysis models of electromagnetic field and temperature field were constructed.Discussed the coupled thermal and electromagnetic field problem taking account of nonlinear materials characteristics related to temperature.(2)The electromagnetic heating process of roller was analyzed,and the temperature distribution and its variation with time were obtained.Discussed the influence of the distance between the coil and the roller on the heating speed of the roller.When the current density is constant,the heating speed increased and the heating time reduced with the raise of current frequency.When the current frequency reached a certain level,the raise of heating speed was not obvious,and the temperature difference between the inner and the outer of the roller increased.When the current frequency is constant,the heating speed and the temperature difference between the inner and the outer of the roller increased with the raise of current density.(3)The regression model between the temperature of roller and the current frequency,current density and heating time was established which provides a mathematical model for the design of subsequent parameters.(4)According to the design requirements,calculate the key parameters,design the fixation machine with electromagnetic.Through the fixation test,the result compared with the traditional cylinder fixation machine is obtained.Based on the above research,the fixation machine with electromagnetic was designed.To compare with the experimental data,the fixation machine with electromagnetic saved 38% than traditional cylinder fixation machine,and shortened the warm-up time.The method of numerical simulation analysis can also be used for the design and optimization of other electromagnetic heating equipment.