FDTD Modeling of EM Field Inside Microwave Cavities

In this book, analysis of electromagnetic (EM) field inside microwave cavities (e.g., oven, autoclave) is presented using finite difference time domain method (FDTD). In this regard, a domestic microwave oven is considered where EM field distribution inside its cavity is determined using FDTD method. Further, the leakage of RF field from the oven door is also estimated at different plane of the door.

The FDTD method is further applied to determine the field distribution inside curved microwave cavities using staircase approach. A hybrid-cylindrical microwave autoclave is considered for the analysis by exciting it with single as well as multiple magnetron sources independently. The hybrid-cylindrical cavity of autoclave is designed here by inserting a metallic plate (table) inside a cylindrical cavity across its length in such way that the EM wave propagation is fully blocked in the region below the plate. The electric field distribution inside autoclave cavity is analysed at 2.45 GHz in xy-, yz-, and zx-planes at different cuts measured along z-, x-, and y-axes, respectively. The field distribution inside the autoclave cavity excited with five source is observed to be almost uniform near the metallic table corresponding to each plane. In order to show the efficient usage of the proposed autoclave for aerospace industry, EM field distribution inside autoclave cavity is studied by keeping a cylindrical sample of glass epoxy inside the cavity.