The study of variability of dynamic properties of the drying chamber of the grain dryer changing the technological parameters of drying

Abstract

The complexity of identification of transfer-function of the drying chamber is connected with a great variety of grain crops, different drying modes of seed, food and feeding grain as well as thermolabile properties of wet material so that in the drying chamber there are grains with different stages of drying and as a consequence of this with different transfer functions. One of the forecasting methods of the dynamic processes of the drying chamber is based on the use of transfer functions of the drying chamber which were got based on the analysis of experimentally obtained transfer characteristics. This paper presents the results of processing of the transfer characteristics of the drying chamber which were got for different parameters of the technological process of drying – heat carrier temperature, grain initial moisture content, initial grain temperature. The transfer functions of the drying chamber for different parameters of the technological process of drying are obtained. For three exposure channels – heat carrier temperature-grain temperature, heat carrier temperature-grain moisture content, heat carrier temperature-worked out heat carrier temperature the variability of the dynamic properties of the drying chamber changing the technological parameters of drying is estimated. Qualitative assessments of inertial and frequency properties are obtained. A significant variability of the dynamic properties of the drying chamber was revealed, which was estimated by scattering of the PI controller settings when the object with the transfer functions under study was included in the automatic control system. The study is performed under the sponsorship of Russian Fundamental Research Fund and Chelyabinsk region as a part of the scientific project № 20-416-740001.