Matching design method and performance evaluation of the organic Rankine cycle system as an alternative to energy-consuming cooling system

Replacing the cooling system of equipment with an Organic Rankine Cycle (ORC) can significantly improve the overall energy efficiency. In this regard, its primary function is to provide a heat exchange capacity that is equivalent to that of the original cooling system, ensuring the normal operation of the associated upper-level equipment. Therefore, a design method matched to the specific heat source characteristics is proposed for ORC systems. A validated ORC simulation model is employed to randomly sample the working fluid mass flow rate and the heat exchanger size gain coefficient, through which response surfaces for heat exchange power and working fluid state are established. The main component parameters and operating parameters of the ORC system are optimized and matched. A case study was conducted by replacing the oil cooler in the excavator hydraulic system with an ORC system, and a comparative analysis of performance was carried out between the original oil cooler and the ORC system. The hydraulic oil temperatures at the inlet and outlet of the heat exchanger are essentially consistent, and the cooling power exhibits nearly identical trends and values. Furthermore, compared to the use of a conventional oil cooler, the application of the ORC system for hydraulic oil cooling enables an additional net output power of 1.9 kW, resulting in a 5.57 % energy saving for the entire excavator. The proposed matching design method provides an effective approach for integrating ORC systems in place of energy-consuming cooling systems, contributing to both energy conservation and emission reduction.