Real-time modelling of wood drying systems - learning from experiment and theory
نویسندگان
چکیده
Predictive control in a wood drying systems is still at an early stage, because of the difficulties with the estimating a temporal moisture distribution for the whole dried lumber. Therefore, based on the dry and wet-bulb temperatures as the state variables the temporal moisture distribution in kiln-dried lumber is determined from numerical solutions of mathematical model for the wood drying systems. This computer model is represented by a set of several partial nonlinear differential equations coupled with the operating functions and a set of several calculating algorithms. The accuracy of the model solutions in a real-time calculation is evaluated by the on-line identification of the operating functions that represent both the system parameters (heat transfer coefficients, thermal conductivity, heat capacity etc) and selected state variables (air temperature, humidity, velocity etc).
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