Mutual influence between cavity and filter on the design of industrial microwave ovens

Continuous-flow industrial microwave ovens usually employ waveguide bandstop filters placed at the open ports to prevent possible hazardous effects on humans. In general, when designing either the heating cavity or the waveguide filter, the mutual influence between both parts is not taken into account. In this work a heating cavity and a doubly corrugated filter are simulated together and separately for different processed materials, and results are compared. It is shown that the performance of the filter is improved when connecting it to the microwave applicator. The electric field distribution is also different in both cases: when simulating the cavity alone or connected to the filter.