基于数值仿真的多馈微波加热温度控制系统

针对常用多模腔加热的不均匀性,对多馈口微波加热进行了研究,提出了一种基于数值仿真分析来设计微波加热系统的方法。通过建立1/2 全尺寸有限元模型进行仿真计算,分析了馈口数量对微波加热的影响,在此基础上采用Bang-Bang 控制策略设计了加热系统。其中,圆柱形谐振腔模型的高度为800 mm,半径为395 mm。腔体周围环形布置10个微波源,通过德拜模型仿真温度变化和测量值进行对比,验证了仿真模型的正确性。不同馈口数的COMSOL仿真结果表明,馈口数为4时,温度变异系数(COV)为0.0897,相比于一个馈口的情况,温度的均匀性提高了10.5%。通过实验测试了微波加热系统性能,实验结果表明,媒质温度能得到合理控制。

Multi-feed Microwave Heating Temperature Control System Based on Numerical Simulation

Aiming at the non-uniformity of common multi-mode cavity heating, the multi-feed microwave heating is studied. A method based on numerical simulation analysis to design microwave heating system is proposed. By establishing a 1/2 full-scale finite element model to simulate the temperature field and analyzing the influence of the number of feed ports on temperature uniformity, the microwave heating system is designed based on Bang-Bang control strategy. The cylindrical cavity model has a height of 800 mm and a radius of 395 mm. Ten microwave sources are arranged around the cavity, and the temperature variation and measured values are simulated by Debye model to verify the correctness of the simulation model. The COMSOL simulation results of different feed ports show that the temperature COV (Coefficient of Variation) is 0.0897 when the number of feed ports is 4. Compared with a feed port, the temperature uniformity is improved by 10.5%. Finally, the performance of the microwave heating system is tested by experiments. The experimental results show that the sample temperature can be reasonably controlled.