Numerical Study of the Effect of Peak Cooler Structure on Airflow and Efficiency of Dry Cooling Tower

Document Type : Original Article

Authors
Mohammad Reza Zangooee Motlagh 1
Seyed Mohammad Javadi 2
1 Department of Mechanical Engineering,Faculty of Engineering, Bozorgmehr University of Qaenat, Qaen, Iran.
2 Department of Mechanical Engineering, Faculty of Advanced Technologies, Quchan University of Technology, Quchan, Iran
10.22034/stme.2025.499712.1097
Abstract
In dry cooling towers of power plants, the presence of a peak cooler is essential to increase the efficiency of cooling systems and improve thermal performance in high-temperature conditions. Also reversing the flow, protect the surrounding heat exchangers from freezing in winter. The appropriate position of this structure and its effect on performance has the particular importance. In this paper, the effect of the peak cooler structure on airflow and the efficiency of the dry cooling tower has been studied. For this purpose, buoyancy-driven flow considering heat transfer from the tower radiators for two cases, with and without a peak cooler, was simulated using ANSYS Fluent 22 software. In this paper, the turbulence and buoyancy effects is considered using k-ε model, as well as with using  radiator boundary condition, the effect of pressure drop and heat transfer of the radiator is considered. The results show that the peak cooler structure has a significant negative impact on the flow rate inside the tower and consequently reduces heat transfer from the delta-shaped heat exchangers around the tower (excluding heat transfer from the heat exchangers inside the peak cooler). Also, due to vortex flows around the peak cooler, the flow rate over the delta-shaped heat exchangers decreases approximately 8%. With despite of the decrease in flow rate and heat transfer from the delta-shaped radiators due to the structure of peak cooler, the total flow rate of the tower and its heat transfer increases because of the using the fan inside the peak cooler and increasing 10% in the radiator surface area. The negative effects can be reduced by moving them towards the center of the tower.
Keywords
Cooling Tower
Airflow
Buoyancy
Peak Cooler
Simulation
Subjects
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Science and Technology in Mechanical Engineering
Volume 3, Issue 2 - Serial Number 5
January 2025
Pages 173-191

  • Receive Date 13 January 2025
  • Revise Date 16 March 2025
  • Accept Date 14 April 2025
  • First Publish Date 14 April 2025
  • Publish Date 14 April 2025