Dielectric measurements between 0.1 to 10 MHz were obtained using an HP 4192A Impedance analyzer for switchgrass and corn stover. For each material, the measurements were obtained at four moisture content levels and three bulk densities. Dielectric properties of these materials could be calculated based on admittance readings and each variable was significant for dielectric constant and loss factor measurements. Dielectric variables were able to be used moisture content and bulk density predictions for both materials. For switchgrass, moisture content was predicted with R2 = 0.94 and RMSE = 0.052, while for density was predicted with R2 = 0.85 and RMSE = 0.0323. For corn stover, moisture content was predicted with R2 = 0.90 and RMSE = 0.0315, whereas, for bulk density, the prediction had a R2 =0.87 and RMSE = 0.0068. The results showed that dielectric measurements have good potential for predicting moisture content and bulk density although further investigation is required for a wider range of frequencies, moisture content, and bulk density levels.
Available at: http://works.bepress.com/stuart_birrell/50/
This proceeding is from 2015 ASABE Annual International Meeting, Paper No. 152160026, pages 1-13 (doi:10.13031/aim.20152160026). St. Joseph, Mich.: ASABE.