Modified thermo-ecological optimization for refrigeration systems and an application for irreversible four-temperature-level absorption refrigerator

In this study, a modified ecological function is presented for four-temperature-level absorption refrigerators, and an absorption refrigerator has been optimized using this function. An equivalent system was initially identified, followed by the application of the first and second laws of thermodynamics. Next, the optimization results were interpreted. The results of the optimization process, optimum point of xH, xR, aH, and aR, were defined as 0.87, 0.58, 2.41, 0.25, respectively. In addition to that, the effects of xH, xR, aH, aR, Ta, Tc, Te, and Tg were shown according to exergy destruction, ecological function, coefficient of performance, and cooling load. As a result, it was understood that especially the xH, parameter, and the generator temperatures are the variables of the system that require special attention because, at some points, they cause that generator and absorber transfer heat in the opposite direction they need to do.