Article ID: 21-45DE_OA
The purpose of a heat transformer cycle is to extract heat at high temperature by utilizing waste heat at low temperature level. The heat generated during the adsorption of high-pressure water vapor raises the temperature of the external fluid to be used flowing in the adsorption reactor. However, since the heat input during preheating of the reactor and the heat removal during precooling are large, therefore, the heat capacity seems to affect the performance. In this study, first, thermodynamic analysis of the equilibrium cycle was performed to predict the amount of extracted heat from a low heat capacity reactor. The heat capacity was 20% smaller than that of the conventional reactor, and as a result, the output heat was 20% higher. Therefore, it was clarified that the decrease in heat capacity directly led to an increase in output heat. In addition to reducing the heat capacity, the effect of improving performance by heat recovery was also significant. The effect was almost the same as obtaining the upper limit of the output heat achieved by zeroing the heat capacity of the reactor. Moreover, from the viewpoint of exergy, heat recovery was important to enable high temperature extraction.