volume | PIER Journals

Abstract

Microwave heating, widely employed in the food industry, offers significant advantages due to its volumetric heating capabilities. However, its efficiency is often hindered by non-uniform heating patterns. This study aims to analyse heating patterns in a rectangular, single-fed domestic microwave oven, leveraging cost-effective methodologies. Theoretical analyses, electromagnetic simulations, and experimental measurements were conducted to characterise the resonant modes within an empty cavity and with a load. The mathematical computation of multiple mode superposition within the cavity was performed for two domestic microwave ovens. Mathematical and experimental analyses demonstrate a close agreement in results. The findings reveal that mode distribution, influenced by cavity dimensions, load properties, load placement, and magnetron characteristics, significantly impacts heating patterns. This study helps us understand that in spite of the dynamic nature of magnetron, it is important to superimpose multiple resonant modes prevalent within the cavity to understand influences on microwave heating pattern of any food materials.

1. Bradshaw, S., S. Delport, and E. van Wyk, "Qualitative measurement of heating uniformity in a multimode microwave cavity," Journal of Microwave Power and Electromagnetic Energy, Vol. 32, No. 2, 87-95, 1997.
doi:10.1080/08327823.1997.11688328 Google Scholar

2. Ye, Jinghua, Chun Zhang, and Huacheng Zhu, "A temperature-control system for continuous-flow microwave heating using a magnetron as microwave source," IEEE Access, Vol. 8, 44391-44399, 2020.
doi:10.1109/access.2020.2978124 Google Scholar

3. Monzó-Cabrera, Juan, J. L. Pedreño-Molina, and A. Toledo, "Feedback control procedure for energy efficiency optimization of microwave-heating ovens," Measurement, Vol. 42, No. 8, 1257-1262, 2009.
doi:10.1016/j.measurement.2009.04.006 Google Scholar

4. Song, Yiwen, Hao Pan, Longyuan Ge, Lili Qiu, Swarun Kumar, and Yi-Chao Chen, "Microsurf: Guiding energy distribution inside microwave oven with metasurfaces," Proceedings of the 30th Annual International Conference on Mobile Computing and Networking, 1346-1360, Washington D.C., USA, 2024.
doi:10.1145/3636534.3690697

5. Yang, Ran, Aly E. Fathy, Mark T. Morgan, and Jiajia Chen, "Development of online closed-loop frequency shifting strategies to improve heating performance of foods in a solid-state microwave system," Food Research International, Vol. 154, 110985, 2022.
doi:10.1016/j.foodres.2022.110985 Google Scholar

6. Chen, Shujin, Shaodou Cen, Renlong Liu, Changyuan Tao, Shenghui Guo, and Guo Chen, "Microwave reactor with combined rigid and flexible stirring paddles for improving fluid heating uniformity in soft manganese Ore leaching processes," ACS Omega, Vol. 8, No. 45, 42367-42378, 2023.
doi:10.1021/acsomega.3c04679 Google Scholar

7. Guzik, Paulina, Piotr Kulawik, Marzena Zając, and Władysław Migdał, "Microwave applications in the food industry: An overview of recent developments," Critical Reviews in Food Science and Nutrition, Vol. 62, No. 29, 7989-8008, 2022.
doi:10.1080/10408398.2021.1922871 Google Scholar

8. Yang, Biao, Hongbin Huang, Liexing Zhou, and Huaiping Jin, "Method for solving the microwave heating temperature distribution of the TE10 mode," Processes, Vol. 10, No. 7, 1377, 2022.
doi:10.3390/pr10071377 Google Scholar

9. Su, Tianyi, Wenqing Zhang, Zhijun Zhang, Xiaowei Wang, and Shiwei Zhang, "Energy utilization and heating uniformity of multiple specimens heated in a domestic microwave oven," Food and Bioproducts Processing, Vol. 132, 35-51, 2022.
doi:10.1016/j.fbp.2021.12.008 Google Scholar

10. Pitchai, Krishnamoorthy, Sohan L. Birla, David Jones, and Jeyamkondan Subbiah, "Assessment of heating rate and non-uniform heating in domestic microwave ovens," Journal of Microwave Power and Electromagnetic Energy, Vol. 46, No. 4, 229-240, 2012.
doi:10.1080/08327823.2012.11689839 Google Scholar

11. Ahn, Seong-Hyeop, Chang-Hyun Jeong, Dong-Min Lim, and Wang-Sang Lee, "Kilowatt-level power-controlled microwave applicator with multiple slotted waveguides for improving heating uniformity," IEEE Transactions on Microwave Theory and Techniques, Vol. 68, No. 7, 2867-2875, 2020.
doi:10.1109/tmtt.2020.2977645 Google Scholar

12. Hill, D. J., C. D. Rudd, and M. S. Johnson, "Design and application of a cylindrical TM020 mode applicator for the in-line microwave preheating of liquid thermosets," Journal of Microwave Power and Electromagnetic Energy, Vol. 33, No. 4, 216-230, 1998.
doi:10.1080/08327823.1998.11688379 Google Scholar

13. Birla, Sohan, Krishnamoorthy Pitchai, Jeyamkondan Subbiah, and David D. Jones, "Effect of magnetron frequency on heating pattern in domestic oven," International Microwave Power Institute's 44th Annual Symposium, Denver, Colorado, USA, 2010.

14. Luan, Donglei, Yifen Wang, Juming Tang, and Deepali Jain, "Frequency distribution in domestic microwave ovens and its influence on heating pattern," Journal of Food Science, Vol. 82, No. 2, 429-436, 2017.
doi:10.1111/1750-3841.13587 Google Scholar

15. Zhou, Xu, Patrick D. Pedrow, Zhongwei Tang, Stewart Bohnet, Shyam S. Sablani, and Juming Tang, "Heating performance of microwave ovens powered by magnetron and solid-state generators," Innovative Food Science & Emerging Technologies, Vol. 83, 103240, 2023.
doi:10.1016/j.ifset.2022.103240 Google Scholar

16. Zhou, Xu, Zhongwei Tang, Patrick D. Pedrow, Shyam S. Sablani, and Juming Tang, "Microwave heating based on solid-state generators: New insights into heating pattern, uniformity, and energy absorption in foods," Journal of Food Engineering, Vol. 357, 111650, 2023.
doi:10.1016/j.jfoodeng.2023.111650 Google Scholar

17. Meredith, Roger J., Engineers' Handbook of Industrial Microwave Heating, No. 25, 1-192, IET, 1998.
doi:10.1049/pbpo025e

18. Barham, Joshua P., Emiko Koyama, Yasuo Norikane, Noriyuki Ohneda, and Takeo Yoshimura, "Microwave flow: A perspective on reactor and microwave configurations and the emergence of tunable single-mode heating toward large-scale applications," The Chemical Record, Vol. 19, No. 1, 188-203, 2019.
doi:10.1002/tcr.201800104 Google Scholar

19. Carvalho, F., A. Kotrashetti, and K. Bhattacharyya, "Investigation of heating in microwave cavities: Insights, evolution, and advancements," IETE Journal of Research, 1-16, 2025.
doi:10.1080/03772063.2025.2567602 Google Scholar

20. Nott, Kevin P., Laurance D. Hall, John R. Bows, Michael Hale, and Maria L. Patrick, "Three-dimensional MRI mapping of microwave induced heating patterns," International Journal of Food Science and Technology, Vol. 34, No. 4, 305-315, 1999.
doi:10.1046/j.1365-2621.1999.00286.x Google Scholar

21. Antuono, C., L. Sito, E. Calzone, D. El Dali, M. Migliorati, A. Mostacci, V. R. Marrazzo, G. Breglio, G. Rumolo, and C. Zannini, "A novel approach for measuring transverse beam-coupling impedance in particle accelerator systems utilizing the bead-pull technique," IEEE Transactions on Instrumentation and Measurement, Vol. 73, 1-9, 2024. Google Scholar

22. Sun, M. H., K. A. Wickersheim, A. Kamal, and W. R. Kolbeck, "Fiberoptic sensor for minimally-perturbing measurement of electric fields in high power microwave environments," MRS Online Proceedings Library, Vol. 189, No. 1, 141-145, 1990.
doi:10.1557/proc-189-141 Google Scholar

23. Ng, K. H., "Microwave ovens: Mapping the electrical field distribution," Medical Laboratory Sciences, Vol. 48, No. 3, 189-192, 1991. Google Scholar

24. Kharkovsky, S. N. and U. C. Hasar, "Measurement of mode patterns in a high-power microwave cavity," IEEE Transactions on Instrumentation and Measurement, Vol. 52, No. 6, 1815-1819, 2003.
doi:10.1109/tim.2003.820453 Google Scholar

25. Metaxas, A. C. and R. J. Meredith, Industrial Microwave Heating, 4-67, IET, 1983.
doi:10.1049/pbpo004e

26. Tian, Wenyan, Xuxin Feng, Lin Gao, Kexin Chen, Yongjia Chen, Jiamin Shi, and Hailing Lao, "Improvement of microwave heating uniformity using symmetrical stirring," Symmetry, Vol. 17, No. 5, 659, 2025.
doi:10.3390/sym17050659 Google Scholar

27. Mehdizadeh, Mehrdad, Microwave/RF Applicators and Probes: For Material Heating, Sensing, and Plasma Generation, 2nd Ed., 1-363, William Andrew, 2015.

28. Hazervazifeh, Amin, Ali M. Nikbakht, and Shahriar Nazari, "Industrial microwave dryer an effective design to reduce non-uniform heating," Engineering in Agriculture, Environment and Food, Vol. 14, No. 4, 110-121, 2021.
doi:10.37221/eaef.14.4_110 Google Scholar

29. Weng, Yu-Kai, Jiunyuan Chen, Ching-Wei Cheng, and Chiachung Chen, "Use of modern regression analysis in the dielectric properties of foods," Foods, Vol. 9, No. 10, 1472, 2020.
doi:10.3390/foods9101472 Google Scholar

30. James, Gareth, Daniela Witten, Trevor Hastie, and Robert Tibshirani, An Introduction to Statistical Learning: With Applications in R, Vol. 103, Springer, 2013.

31. Zheleva, Ivanka and Vesselka Kambourova, "Identification of heat and mass transfer processes in bread during baking," Thermal Science, Vol. 9, No. 2, 73-86, 2005.
doi:10.2298/tsci0502073z Google Scholar

32. Liu, Yanhong, Juming Tang, and Zhihuai Mao, "Analysis of bread dielectric properties using mixture equations," Journal of Food Engineering, Vol. 93, No. 1, 72-79, 2009.
doi:10.1016/j.jfoodeng.2008.12.032 Google Scholar

Ms. Freda Carvalho

Dr. Ashwini Kotrashetti

Dr. Kaustubh Bhattacharyya