MICROWAVE ABSORBING CHAMBER Russian patent published in 1999 - IPC

FIELD: heating, including evaporation, drying, pasteurization, and sterilization, of water-containing materials; final load of microwave oscillator. SUBSTANCE: chamber has absorbing liquid tank and rectangular waveguide section one of whose walls has coupling holes at tank installation point; waveguide section has adapter for transition from rectangular waveguide of cross-sectional area A x B to rectangular waveguide of cross-sectional area A x 0.57 B, 0.8λ_w long, rectangular waveguide section incorporating first portion of A x 0.57 B in cross-sectional area and 2.36λ_w in length, where λ_w is wavelength in rectangular waveguide section, and second portion, 0.53λ_w in length whose wide wall equals A, narrow wall size linearly reduces from 0. 57 B to 0.01 B; nine rectangular coupling holes are provided on wide wall of first and second portions of rectangular waveguide section in parallel to its axis at point of installation of absorbing liquid tank; coupling holes are sealed with low-loss insulating material; size and relative arrangement of coupling holes in waveguide provide for uniform heating of material being treated and matching with microwave oscillator; chamber voltage standing wave ratio is not over 1.3 at considerable variations in ε and tgδ of material under treatment. EFFECT: improved uniformity of absorbing material heating. 2 cl, 2 dwg