A Novel Method by Three Slot Coupling Holes Alternate Working to Improve Microwave Heating Uniformity

Microwave heating is a booming technology in the food industry that has gained attention for its outstanding benefits. However, the problem of uneven heating remains a persistent challenge in practical applications. To solve this problem, this study presents a novel microwave heating method that improves heating uniformity by generating a rotating electric field. However, unlike traditional methods, it does not rely on physical rotation. To illustrate the method succinctly, a structure with three center-symmetric coupling slots was designed. The cyclic activation of these slots results in an effect similar to a port in rotation, generating a dynamic electric field in the resonant cavity so that the microwave energy is absorbed more uniformly. To validate the proposed method, a corresponding multiphysics field simulation model is developed. The heating process was simulated and analyzed by deeply coupling Maxwell's equations with heat conduction equations. Moreover, a well-established system was built for physical experimental validation. The results show that the proposed method surpasses the traditional single-port fixed-position heating with a 79.3% improvement in heating efficiency and a 17.2% improvement in heating uniformity.