THE DISSIPATION TEMPERATURE - A TOOL FOR THE ANALYSIS OF MALFUNCTIONSIN THERMOMECHANICAL SYSTEMS

The aim of this paper is to define and characterize a new parameter, t he dissipation temperature. When a thermal plant component displays an internal deterioration (intrinsic malfunction), its performance gets worse. This fact is reflected in a variation of the internal parameter s that describe its behavior (isentropic efficiency, effectiveness, pr essure and/or temperature ratios, parameter theta [1]). On the other h and, the remaining components of the plant may be affected (by induced malfunctions) because they are working under different operating cond itions with respect to the rated ones. The knowledge of variations of the internal parameters in each component of a thermal plant does not suffice to determine their performance state under these new condition s. Additional information is needed. The dissipation temperature, defi ned as dh/ds when a malfunction occurs, can supply it as is explained in this paper. Moreover, three interesting applications of the dissipa tion temperature are shown: description of an energy system when a mal function occurs; assessment of the importance of an intrinsic malfunct ion in a component; and the analysis of the influence of a malfunction on the exergetic efficiency of a component. (C) 1997 Elsevier Science Ltd.