ABSTRACT
Cooling towers are important components within re-circulating 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, 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.
KEYWORDS
PAPER SUBMITTED: 2021-05-23
PAPER REVISED: 2021-09-23
PAPER ACCEPTED: 2021-09-23
PUBLISHED ONLINE: 2021-11-06
THERMAL SCIENCE YEAR
2022, VOLUME
26, ISSUE
Issue 5, PAGES [3715 - 3728]
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