基于变换光学的微波加热用超表面数值研究

由于单个微波源的功率值有限,工业上往往采用多源微波加热以满足大功率需求。然而,额外 的微波馈口将增加端口间耦合,可能引起微波源损坏。因此,提出一种基于变换光学的新型超表面,使微波在 进入加热腔体的方向上正常传播而在相反方向被阻挡,从而减少功率反射和耦合。在二维数值模型中,采用 反向传播神经网络优化了超表面的介电性能,使得单源和双源微波加热的能量效率分别提高了42. 2%和53. 3%,且 均具有较好的加热均匀性。数值计算结果表明,超表面可工作在2. 45 GHz 频率,具有60 MHz 的带宽,工业应用前 景良好。

Numerical Investigation of Metasurfaces Based on Transformation Optics for Microwave Heating

Due to the power limitation of single microwave source, the multi-source microwave heating is widely adopted in high-power industrial applications. However, the additional microwave feeding ports will increase the port-to-port power coupling, which may damage the microwave sources. In this paper, a novel kind of metasurfaces based on transformation optics is proposed to decrease the power reflection and coupling by transmitting the microwave in the direction of entering the microwave applicator but blocking it in the reverse direction. In the two dimensional numerical model, the dielectric properties of the metasurfaces are optimized by the back propagation neural network and the energy efficiency can be improved by 42. 2% and 53. 3% in the single and dual-port microwave applicators, respectively, both of which have good heating uniformity. The numerical calculation results show that the metasurfaces can work well at 2. 45 GHz with a bandwidth of 60 MHz, which has beneficial industrial application prospects.