Instruments and Systems: Monitoring, Control, and Diagnostics Annotation << Back Modeling and Research of the Pasteurization Process as a Multi-Connected Control Object S.V. RYAZANCEV, E.A. HROMYH, I.A. KOZENKO The development of effective automatic control systems largely depends on the accuracy of the mathematical models of objects used and taking into account the features of the described processes. These include the structure of the interconnections of inputs and outputs, which largely determines the type of system used, the methods of calculating its control part, and, ultimately, the quality of regulation. The paper considers one of the most common processes of the food industry – the process of pasteurization of raw materials. Based on the heat balance equations, a mathematical model of a three-section plate pasteurization and cooling plant is obtained. The development consisted in sequential modeling of each of the sections (regeneration, pasteurization, cooling) and then combining their descriptions. The analysis of the mathematical description made it possible to identify and present in the form of structural diagrams the relationship of the main technological parameters that characterize the quality of the process. It is shown that this process is a multidimensional object with interrelated parameters. The input influences are the flow rates and the initial temperatures of the milk, hot and cold water entering the pasteurizer. The output values are the milk temperatures at the outlet of the regeneration, pasteurization and cooling sections. The calculation of transients relative temperature change of material flow at the outlet sections with a step-like changes of temperatures and flows into the inputs of the device confirmed the structure of interactions between parameters and allowed to quantify the degree of their mutual influence on each other. Keywords: pasteurization, pasteurization and cooling unit, mathematical modeling, heat balance equations, dynamic model, crosslinks, multi-connected control object DOI: 10.25791/pribor.11.2021.1304 Pp. 31-42.