Heating performance of dual-source microwave heating using different frequency shifting strategies in a solid-state...

Area of Science:

• Applied Physics
• Food Engineering
• Microwave Engineering

Background:

• Magnetron-based microwave ovens suffer from nonuniform heating.
• Solid-state microwave heating offers potential for improved efficiency.
• Prior research focused on single-source systems or fixed frequencies in dual-source systems.

Purpose of the Study:

• To experimentally investigate frequency shifting approaches in a dual-source solid-state microwave system.
• To analyze port interactions and heating performance under different conditions.
• To compare heating uniformity with and without a turntable.

Main Methods:

• Investigated four frequency shifting strategies: Fixed-frequency, Synchronized-shifting, Inverse-shifting, and Distinct-shifting (2.4-2.5 GHz, 0.01 GHz interval).
• Evaluated system performance under stationary and rotatory conditions.
• Assessed port interactions, microwave power efficiency, and heating uniformity.

Main Results:

• Port interactions depended significantly on microwave frequency and load position, impacting power efficiency.
• All three frequency shifting strategies outperformed fixed-frequency heating.
• A turntable did not enhance heating uniformity when combined with frequency shifting.

Conclusions:

• Frequency shifting is a viable strategy to improve heating performance in dual-source solid-state microwave systems.
• Effective multi-port frequency shifting may render turntables obsolete for achieving uniform heating.
• Further research into optimal frequency shifting strategies is warranted.