Experimental Study On Water Content Detection System Of Rice And Drying Technology Of Tampering In Deep Bed

Rice post-harvest drying is an important processing.Hot air drying is a common dehydration method after rice harvest,and the drying effect directly affects the quality of rice processing and storage in the later period.Tampering drying is an important technology for rice drying.The online detection of moisture content during rice drying can control the drying process of rice,avoid the deterioration of drying quality and improve drying efficiency,which is of great significance for rice drying production.The main research contents and conclusions of this paper are as follows:(1)The flow field and temperature field distribution in the rice hot air deep bed drying chamber were studied by simulation.The distribution of the hot air flow field in the dry rice silo is not uniform,and the air velocity in the dry rice layer is obviously different from that in the non-dry rice layer.The distribution of temperature difference between the dry layer and the middle and upper layer of rice was almost the same,and the temperature of the non-multi-span area was almost the same.The temperature distribution among the dry layers of rice was uniform.(2)To improve the moisture content online detection system in the slow drying process of rice.Based on the working principle of capacitive moisture content on-line measuring system of rice,the network structure of concentric cylinder capacitive sensor plate is improved.The capacitance value generated by the network electrode plate is significantly different from that of the traditional closed electrode plate.However,the network electrode plate can also generate the capacitance value of the same order of magnitude as the ordinary capacitor electrode plate,which can meet the requirements of measuring the change of water content of rice.Moreover,the distribution of the heat flow field and temperature field of the capacitive electrode plate with the improved network structure is more uniform.(3)The dry experiment of rice deep bed fixed by hot air was carried out.The experimental factors including temperature,time,way,moisture content and time were selected.Experiments were conducted to study the effects of various factors on explosion waist growth rate,milled rice rate,germination rate and drying uniformity.It is helpful to increase the drying rate,reduce the temperature gradient and water gradient inside the grain,and improve the drying quality.The temperature,the time,the way and the moisture content of the dried fruit had significant influence on the drying quality,and the change of the drying time had significant influence on the drying quality.