Cooling towers are important components within recirculating cooling water systems. Due to a shortage of freshwater resources, seawater cooling towers are widely used both in manufacturing and everyday life. This paper researches the mechanical draft counterflow wet seawater cooling tower (MDCWSCT), and establishes and verifies a detailed thermal performance calculation model. Referring to the second law of thermodynamics, the heat and mass transfer performance and exergy performance of the seawater cooling tower were studied. The effects of salinity, inlet air speed, and air wet-bulb temperature on the cooling efficiency, thermal efficiency, and exergy efficiency were analyzed. The results show that compared to the air wet-bulb temperature, changes in air speed have more influence on cooling and thermal efficiency under the study conditions. Moreover, the air wet-bulb temperature is the significant parameter affecting exergy efficiency. With an increase in salinity, the cooling, thermal, and exergy efficiency are about 2.40-8.25 %, 1.06-3.09 %, and 2.47-7.73 % lower than that of freshwater, respectively, within an air speed of 3.1-3.6 m/s. With an increase in salinity, the cooling, thermal, and exergy efficiency are about 2.28-8.47 %, 1.03-3.37 %, and 2.44-7.99 % lower than that of freshwater, respectively, within an air wet-bulb temperature of 25-27 ?. Through the exergy analysis of the seawater cooling tower, it is obvious that the heat and mass transfer performance and exergy performance can be improved by selecting the optimum operating conditions and appropriate packing specifications.

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A large amount of waste heat generated in industrial production needs to be discharged by circulating cooling water systems. To save freshwater resources, freshwater cooling towers have been widely replaced by seawater cooling towers in coastal areas, but research on the thermal performance of seawater cooling towers is still relatively less. In this study, a detailed calculation model based on the heat/mass transfer process of seawater-air two-phase counterflow was established, and the reliability of the proposed model was verified. The computer program developed under the VC++ framework was used for the numerical solution of the model. The effects of five inlet parameters on the cooling efficiency and heat dissipation were studied. The simulation resultsshowed that with the increase of salinity, the cooling performance was reduced. When the salinity increased by 10 g/kg, the outlet water temperature rose by about 0.13°C. The wet-bulb temperature increased by 1°C and the cooling efficiency increased by about 0.77%, while total heat dissipation was reduced by about 36.37 kW. When the air-water ratio increased, the cooling performance was improved, but the maximum cooling efficiency was affected by heat load. The change of dry-bulb temperature had little effect on the cooling performance. With the increase of water temperature, the cooling efficiency and heat dissipation increased. The calculation model and simulation results can provide practical guidance for the operation of seawater cooling towers.