3E (Energy–Exergy–Environmental) Performance Analysis and Optimization of Seawater Shower Cooling Tower for Central Air Conditioning Systems

The thermodynamic, exergy and carbon reduction potential of seawater shower cooling towers for central air conditioning systems was investigated under various geometric, physical and environmental conditions. A mathematical model of the shower cooling tower was proposed, and the governing equations considering droplet diameter changes were numerically solved during evaporation. The results showed that compared with the downward-spraying tower, the upward-spraying tower achieved 15.59% higher cooling efficiency, 4.89% higher exergy efficiency and 34.58% higher heat dissipation. Increasing droplet diameter significantly weakened the tower’s cooling capacity, with heat dissipation decreasing by 78.11% as the diameter increased from 1 mm to 2.25 mm. The cooling efficiency, thermal efficiency and exergy efficiency demonstrated consistent declining trends with increasing droplet diameter. Under high-salinity conditions (105 g/kg), compared with standard salinity (35 g/kg), the average reduction of cooling efficiency was 2.96%, and exergy efficiency decreased by 2.73%. The increase in air velocity from 2.5 m/s to 4.0 m/s led to a 13.76% improvement in cooling efficiency and a 22.44% increase in heat dissipation, and exergy efficiency decreased by less than 2%. Through multi-objective optimization analysis, the cooling efficiency increased by 14.69% and exergy destruction decreased by 37.87%, demonstrating significant potential for energy conservation and carbon emission reduction in central air conditioning applications.