Knowing the temperature distribution in silo is a convenient and efficient way to control the process of grain storage.A three-dimensional(3-D)numerical model was used to study the temperature variation in small grain steel silo under quasi-steady state.In this study,experiments were conducted and porous media model was adopted.Results of numerical simulation and experiment were compared and the results indicated that grain temperature was influenced by temperature of the wall,grain stacking height,and the distance between grain and wall.The higher the wall temperature,the more the temperature increases.If the wall temperature is low,the effect of wall temperature on temperature distribution is significant.The temperature at the top part of grain varied obviously with the changes of temperature in air layer.Overall,numerical simulation results coincided with experimental results and the model established in this study is valuable for predicting grain temperature in steel silo.
Yellow maize as raw materials,hot air drying was used to reduce moisture content,and the tempering was implemented after drying.This study aimed to investigate the effects of hot air drying temperature and tempering time on the properties of maize starch.The wet milling was used to extract maize starch.Starch yield,protein content,amylose and amylopectin content,transparency and coagulation,solubility index and swelling power,color,pasting properties,and gelatinization properties were researched.The results showed that when the hot air temperature increased,the properties such as starch yield,amylopectin content,transparency,solubility,swelling power,whiteness decreased,and properties such as protein content and amylose content,coagulation,gelatinization temperature increased.Compared to drying temperature,tempering time has a less remarkable effect on the maize starch properties.The maize starch with better whiteness,solubility,swelling power could be obtained by adjusting tempering time.
