The modeling and control of a reheating furnace

A model of a walking-beam reheating furnace is constructed. The model consists of three sub-models, automatic combustion control model (ACC), dynamic model of the combustion process, and control loops model. The ACC model calculates the setpoints of furnace temperature such that the slabs in the furnace can be heated to discharging temperature. A dynamic model, which is mainly discussed in the paper, describes the behavior of the furnace under the state of rolling line and fuel flux provided by the control loop model. The control loop model, or distributed control system model control the fuel flux of each zone according to setpoints of furnace temperature and state of the furnace. The structure of the model is discussed in detail in the paper. The numerical examples show the validity of the model. The model can be used to develop new energy-saving techniques, or to realize quality optimization etc.