The Study On Computing Model And Simulation Of The Adsorption And Desorption Isotherms Of Rice

With rice as the research object, based on the agricultural microbiology, focusing on rice storage, drying and other management processes, the paper focuses on rice adsorption and desorption data and parameters at different temperature conditions and analyses its adsorption and desorption isotherms change to establish the adsorption and desorption isotherms of the computational model by employing system analysis theory and mathematical modeling technique. In the process, the fuzzy recognition and evolutionary algorithm is applied to the model optimization and simulation software is programmed to realize the computer simulation of rice adsorption and desorption isotherms so as to provide scientific parameters for rice processing, storage, and management.Rice adsorption and desorption capacity is tested mainly through adsorption and desorption isotherms which in rice drying can be used to determine the appropriate drying end point and calculate the drying time; in storage the adsorption isotherm can be used to determine the safe storage moisture content, control storage environmental conditions. the research measures rice absorption and desorption data in 20℃, 30℃, 40℃, maps the corresponding adsorption and desorption isotherms, analyses the quantitative relationship between rice paddy water activity in storage, equilibrium moisture content of rice and rice storage operations, confirms rice storage conditions with the given temperature combined with the analysis of rice isosteric heat Qa (DTA enthalpy) and the adsorption thermodynamic binding energy L, employs nonlinear regression and SAS NLIN parameter estimation and other mathematical methods on the adsorption and desorption data to establish a rice adsorption and desorption isotherm model. The research also optimizes the model by adopting the evolutionary calculation based on population classification and elaborates improved evolutionary algorithm operators, concludes that revised GAB model is the best one to describe rice adsorption and desorption, and programs simulation software to simulate rice adsorption and desorption isotherms. The result indicates that at the same temperature conditions, the equilibrium moisture content of rice ME increases with the rise of relative humidity RH or water activity Aw, but in the adsorption and desorption isotherm, the rate of change in different segments varies: at the beginning segment change rate is faster, slow rate of change in the middle section, the last paragraph of the isotherms, the change rate has increased, at the bottom of adsorption and desorption isotherms, there is adsorption hysteresis; in the same humidity RH conditions, the rice equilibrium moisture content increases with the decline of temperature Me. The adsorption and desorption isotherm shows high temperature isotherm is below the low temperatures isotherm; through the analysis of the rice water activity Aw, Qa isosteric heat and adsorption thermodynamic parameters such as binding energy, the conclusion is that rice Qa and L gradually decrease with the increase of Me and Aw, while rice L value is also related to temperature, with the same Aw value, the higher the temperature is, the larger L value is, but in the lower temperature range, the temperature has less influence on the value of L.Affected by many factors, rice storage and drying is a complex and unique multi-factor dynamic management processes, so it is difficult for grain storage management to make comprehensive consideration of multi-factor interaction, quantitative storage measures. With the development of information technology, digital agriculture is on the rise. Digital technology reshaping the modern agricultural production will fundamentally change the backwardness of traditional agricultural production, boost the change of growth patterns of agricultural production and agricultural economic structure adjustment and optimization, solve increasingly acute contradiction between supply and demand in agricultural production in our country as well as improves the quality of the human environment.