Abstract
［Objective］ To address the limitations of traditional single -point moisture measurement in complex drying environments,a multi -conductor array capacitor device was designed for moisture content measurement inside a grain dryer.［Methods］ An array of 8 conductor rods was arranged to measure the capacitance between each pair of adjacent rods,from which the average dielectric constant in the inter -rod regions was calculated to enable real -time moisture monitoring during the grain drying process.［Results］］ High -precision capacitance measurements were achieved using an FDC 2214 capacitive sensor controlled by a Raspberry Pi Pico W.The relationship between the dielectric constant in regions with varying moisture content and the corresponding water weight was validated,generating a two -dimensional dielectric constant distribution map.In environments with uneven humidity distribution,the device rapidly and stably detected moisture diffusion and accurately fitted the improved Dobson model.During the fitting process,the maximum standard deviation of the dielectric constant was 3.98,with an average value of 1.27.［Conclusion］ By adjusting the physical structure of the test setup,the device can measure the average moisture distribution in any spatial unit of grain.
Publication Date
6-2-2025
First Page
97
Last Page
104
DOI
10.13652/j.spjx.1003.5788.2024.80983
Recommended Citation
Cong, LIU; Jue, LIU; Dachang, CHEN; and Chao, FANG
(2025)
"A multi-conductor array capacitor device for grain dryers and its measurement analysis,"
Food and Machinery: Vol. 41:
Iss.
4, Article 12.
DOI: 10.13652/j.spjx.1003.5788.2024.80983
Available at:
https://www.ifoodmm.cn/journal/vol41/iss4/12
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