## 1 Introduction
In large-scale HVAC systems, recuperators can recover waste heat from indoor air units or outdoor air intakes for use in beneficial tasks such as heating or hot water production [1]. Furthermore, exergy analysis and irreversibility calculations have been conducted in another section of this study. These calculations were performed separately for each fluid used in the ORC design, and the results were compared. Exergy is a concept in thermodynamics that measures the quality or availability of energy [28]. It indicates how efficiently energy is utilized compared to the conditions of the system's surroundings. Higher exergy indicates that energy is more practical and of higher quality, whereas lower exergy suggests less valuable energy. Exergy analysis of a cooling system is used to assess the system's energy efficiency, identify energy losses, and optimize system performance. Exergy analysis is a crucial tool for improving the energy efficiency of cooling systems and using resources more effectively. Irreversibility, in thermodynamics, indicates how effective a thermodynamic process is or how efficiently a process occurs. It shows how much loss or energy waste is inherent in a process. In thermodynamics, the more irreversible a process is, the less efficient it is. The irreversibility value of a cooling system is used to determine how effective the system is or how efficient the process is. This value is obtained by comparing the actual and ideal processes [29]. Water is the preferred working fluid for large-scale Rankine cycles that use high-temperature energy sources in a wide range of efficient cycle configurations, from saturated nuclear power plants to coal-fired ultra-supercritical cycles. However, steam's thermodynamic features require multistage, capital-intensive turbines, complex plant systems, and liquid formation during expansion; these limitations render steam an unsuitable working fluid for low temperature and power output applications. The ORC aims to generate power from moderate-temperature, distributed energy sources cost effectively. This is accomplished by selecting a suitable working fluid capable of facilitating a basic plant arrangement and a low-cost turbine without liquid formation. Although the traditional Rankine cycle (RC) and the organic Rankine cycle (ORC) share the same principle, they have many differences [30]. A comparison between the RC and ORC is provided in Table 2. \begin{table}
\begin{tabular}{c c} \hline \hline
**RC** & **ORC** \\ \hline medium/high temperature & medium/low temperature \\ large heat sources & small heat sources \\ higher critical temperatures & lower critical temperatures \\ higher critical pressures & lower critical pressures \\ lower prices of fluids & higher prices of fluids \\ lower thermal efficiency & higher thermal efficiency \\ complicated turbo machinery & less complicated turbo machinery \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison between RC and ORC. In this study, a traditional RC and ORC system designed to recover the energy released during the full-load operation of a ship engine is presented. The designed system incorporates eleven working fluids, comprising four dry, two wet, and five isentropic conditions. In this work, the Engineering Equation Solver (EES) [M1] [HK2] (V11.898) and NIST Reference Fluid Thermodynamic and Transport Properties Database (REFPROP) (V10) commercial software are employed to obtain the thermophysical properties of each refrigerant used in the RC, and calculations are performed accordingly.