Experimental assessment of power efficiency for microwave multimode ovens with mode stirrers and sample movement

In this work, an experimental study to assess power efficiency in the 2.45 GHz ISM band for microwaveheating ovens that use both sample movement and mode stirrer is carried out. Several materials have been employed as dielectric loads such as marble, wood and polyester resin. Two different stirrer configurations have been used and compared during measurements. Sample movement has also been evaluated since it is a usual technique when trying to obtain uniform patterns in materials. Obtained results show that efficiency values above 95% can be obtained within microwave ovens. Finally, it has been shown that power efficiency can be optimized by properly choosing sample location or stirrer angular position within the oven and the relationship between cavity dimensions and used frequency.