|Budget Amount *help
¥3,400,000 (Direct Cost : ¥3,400,000)
Fiscal Year 2000 : ¥200,000 (Direct Cost : ¥200,000)
Fiscal Year 1999 : ¥200,000 (Direct Cost : ¥200,000)
Fiscal Year 1998 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1997 : ¥2,500,000 (Direct Cost : ¥2,500,000)
The purpose of this study is to investigate the formative mechanism of uneven moisture distribution that cause mold and degradation of grain in storage silo and develop the monitoring system to detect abnormal moisture distribution. Unevenness of grain moisture forms during storage, even if a silo was charged with uniform moisture grain. We assumed the temperature difference between silo wall and grain causes the moisture movement. Firstly, we measured the temperature and humidity of the upper airspace and outside wall of a grain silo. Using the measured values and model experiment, we simulated the moisture movement in the grain silo. We reached the conclusion that main cause for the uneven moisture distribution is the dew condensation and the water droplet from wall or ceiling into the grain Iayer rather than the direct water movement between grain layers. Secondly, to monitor the irregularity of grain moisture distribution, inserting long metal bar etc.into the thick grain layer, time-domain spectroscopy TDR and TDT were experimented. As the reflected wave is generated in the boundary where the moisture differs, from the reflected wave form abnormality of the moisture distribution was detected. From the propagation delay time, the average moisture was detected at least to grain layer of about 2m. Thirdly, with non-contact measurement using horn antennas, same experiments of time-domain spectroscopy TDR and TDT were experimented. The average moisture was detected at least to grain layer of about 1m by TDT and anomalous reflection based on the moisture irregularity was detected to the depth of about 20cm from surface layer by TDR.Fourthly, on moisture distribution of surface grain layer, experiments which obtain the spectral image using the multiple wavelengths near 970nm of the water absorption band was carried out. As the result of the visualization processing, the moisture distribution image of the grain layer surface was obtained.