Matematické modelování přenosových jevů na rozhraní dvou tekutin využívaných v procesních systémech

Abstract

The essence of the presented dissertation is the research of processes taking place in a hot-water accumulator, where two fluids of different temperature come into contact. During this process, degradation processes occur which reduce the efficiency of energy storage in the form of hot water. The dissertation is structured into several parts, the continuity of which forms a coherent procedure leading to the fulfilment of the main objectives of the thesis. The first part focuses on the current EU energy policy and the current status of storage devices. Furthermore, the emphasis is placed on understanding the general context of the designed decentralised energy unit project, presents an innovative solution for the internal installation, including a search of similar installations, and presents the general knowledge of hydromechanics, thermomechanics, elasticity and strength and numerical modelling necessary for understanding the problem. The second part of the present dissertation deals with the development of a numerical model simulating heat transfer through a moving membrane. For this purpose, a completely new methodology had to be developed to approach this physical problem, since a similar problem has not been described in the literature before. Thus, a detailed description of the numerical model is given as well as the parameter settings for the so-called dynamic network. Furthermore, an attempt to derive a methodology for validating the numerical model using dimensionless criteria is presented. The third part is devoted to the design of a functional sample of a hot water battery in the laboratory, the design of the measurement line. A solution for measuring the temperature inside the battery using DTS systems is presented and finally the results of the work and their evaluation are presented. The contributions of the dissertation to the discipline and to practice are summarized, and recommendations for further research on the subject are suggested.