THREE-DIMENSIONAL TRANSIENT HEAT, MASS, AND MOMENTUM TRANSFER MODEL TO PREDICT CONDITIONS OF CANOLA STORED INSIDE SILO BAGS UNDER CANADIAN PRAIRIE CONDITIONS: PART I. SOIL TEMPERATURE MODEL

摘要

Silo bags have been used by Canadian farmers in the last few years to temporarily store cereal grains, pulses, and oilseeds for up to one year. It is difficult to install temperature and moisture cables inside silo bags or conduct sampling because any cutting of the silo bag damages its hermeticity. Mathematical models could be used to predict spoilage during storage, and the accuracy of mathematical models is influenced by soil temperature. In this study, soil temperature models were developed based on the energy balance on the surface of the ground and heat conduction equations (HCE). The surface of the ground was covered with snow during winter and with vegetation during summer. The developed soil models were coupled with the developed three-dimensional transient heat, mass, and momentum transfer models inside silo bags. The developed models were validated using weather data (solar radiation, temperature, relative humidity, wind speed, and snow covering) and temperatures collected inside bulk canola in silo bags with 9.1% and 10.5% moisture contents. The prediction accuracy associated with the HCE models was compared with that associated with Fourier series, which has been used in the literature. The HCE models developed in this study had higher prediction accuracy than the Fourier series. The maximum absolute difference and average absolute difference between the measured and predicted (by the HCE models) canola temperature at 10 cm height of the canola from the bottom of the silo bag were 3.23 degrees C and 1.79 degrees C +/- 0.04 degrees C, respectively.