Thermoconomic analysis of cogeneration installation (cgam) based on theory of the exergetic cost

Abstract

Modern cogeneration systems are complex energy-technology complexes with a high degree of energy recovery. Pre-design analysis of these systems must take into account both the economic and thermodynamic components of the process of energy conversion. The most scientifically grounded basis for the development of recommendations for the design of aggregates of the cogeneration system is the modern method of thermoeconomic analysis. On the basis of the theory of exergetic cost, a thermoelectric model of a cogeneration unit is constructed, which takes into account the nonequivalence of exergy losses, which is related to the structural-topological features of the technological scheme. The thermoeconomic model has a hierarchical structure, which is a thermodynamic model, which is necessary for the determination of exergy flows, as well as an exergo-topological model that establishes, by means of flow graphs, the interconnections between exergetic flows in the installation. For visualization of the thermoelectric model, a functional exegetic flow diagram of a cogeneration unit is proposed, which helps to perform the separation of flows for a qualitative sign "fuel" - "product" of the element. In order to further coherent assessment of the exergetic and economic indicators of the system to the general thermoelectric model, the functions of the capital cost of the elements can be involved.On the basis of the numerical implementation of the thermoelectric model in the technological scheme of the installation areas are identified that have an excessive specific consumption of exergy, anomalies and dysfunctions for each element of the scheme. With the involvement of methods of the theory of experiment planning, regression models of the exergy efficiency of the installation were constructed depending on the determining factors, the factor analysis was performed and the interrelated influence of them on the exergy efficiency of the installation was determined.