Cylindrical microwave heating applicator with only two modes

A microwave containment chamber for a microwave applicator for heating a load, the chamber comprising:

• a) a top wall;
• b) a bottom wall;
• and
• c) a generally cylindrical side wall connected to the top wall, and sealed sufficiently to contain microwaves, the cylindrical side wall having an interior diameter;
• wherein the interior diameter of the cylindrical side wall is sized to support a microwave field having first and second transverse magnetic modes, and characterized by the absence of transverse electric modes, each transverse magnetic mode having a respective guide wavelength, and wherein the guide wavelength of the first transverse magnetic mode is substantially twice the guide wavelength of the second transverse magnetic mode.

A microwave applicator for heating a load, the applicator comprising:

• a) a generally cylindrical microwave containment chamber having a continuous side wall, a generally planar top wall, and a bottom wall, the side wall connecting the top wall and the bottom wall, the top, bottom, and side walls sealed and secured together to contain microwave energy, the containment chamber having an interior diameter;
• b) a microwave energy source for generating microwave energy at a frequency substantially equal to 2450 megahertz;
• c) a feed structure connected between the microwave energy source and the containment chamber for coupling the microwave energy from the energy source to the containment chamber;
• wherein the interior diameter of the containment chamber is sufficiently close to 9.17 inches to support a microwave field having only a TM.sub.02 first transverse magnetic mode and a TM.sub.11 second transverse magnetic mode, each mode having a respective guide wavelength, and such that the guide wavelength of the first mode is substantially equal to two times the guide wavelength of the second mode.