The relevance of this work is conditioned by the need for maintaining a given temperature at the outlet of a heat exchanger under the conditions of variable flow rate and composition of the feedstock. This work reviews the methods for improving the heat exchanger control. The parameters of the control object are selected and its features are determined. A dynamic model of a heater with a steam space (shell-and-tube evaporator) applied for heating the gasoline fraction at the outlet of the topping column of the oil stabilization unit is obtained. The part of the distillate and fractional composition of the gasoline fraction, which is a disturbing factor, are determined. The mathematical model of the shell-and-tube evaporator is presented as an object with lumped parameters in the form of heat balance in a differential form taking into account transport delay. The heat transfer coefficient is determined from the side of gasoline fraction for the bubble boiling mode and from the side of stripped oil for the turbulent mode. A single-loop automated control system (ACS) and an ACS with the participation of the obtained model are implemented within Simulink. In the first case, the object model is represented in the canonical form in the state space. The intermediate signals (from matrix feedback amplifiers) are used as the control actions. In the second case, a combined temperature control system is developed at the outlet of the heat exchanger. The output signal of the model is supplied as a current parameter to controller 2, which generates a control signal that compensates for the disturbance. The task of controller 2 is the output signal of controller 1, which adjusts the operation according to the output temperature of the object. A comparison of the control methods with the use of standard controllers and with the participation of the developed object model is given. It is shown that the indicators of the transition process are higher when applying the models in the control.
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