Abstract
The performance of a grain-cooling system for reducing the heat to which wheat and rice grains stored in silos are subjected through the exterior surface of the silo wall was evaluated. This system can be used when the grain temperature and the outside temperature are both high at the start of the storage process. Grain-cooling systems have seen numerous advances. However, few studies have investigated the effects of the operating conditions. We examined the basic performance of the grain-cooling system using an actual silo and obtained the following results. The cooling air introduced into the test silo used cooled the silo (storage capacity of 300 t) to 16–18 ℃ in 17–44 h, with the humidity being approximately 75 %. However, when examining the performance of the cooling system, we overlooked the process for cooling the dryer and stored 250 t of paddy grains in the test silo. The temperature of the stored paddy grains was initially approximately 36 ℃ but decreased to 20 ℃ in approximately 33 h. The results of these examinations confirm the silo-cooling effect of the system. However, it should be noted that the cooling time as well as the condensation of dew on the inner wall of the silo should also be taken into consideration during performance evaluation.
