• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.12
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• pp.1018-1027
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• 2003

This study treats the analysis of the performance and the design of plume abatement wet/dry cooling tower with dry type heat exchanger using a numerical method. A two-dimensional analysis is performed using the finite volume method for mechanical draft counterflow and crossflow tower. For a coupling problem between water and air system, a turbulent two phase flow is considered. Effectiveness-NTU method is used for modeling of the dry type heat exchanger. The parameter change simulations of the outer wall shape, the relative flowrate of air, and attachment of an air mixer are performed to examine the effect on plume abatement. It is found that if the relative air flowrate ratio and the adequate air mixer type are chosen well in addition to the ratio of water to air flowrate, the loss of the cooling capacity and the additional cost are reduced and the plume is abated.

• International Journal of Air-Conditioning and Refrigeration
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• v.13 no.2
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• pp.61-70
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• 2005

This study treats the numerical analysis of performance and design for plume abatement wet/dry cooling tower with a dry type heat exchanger. A two-dimensional analysis is performed using the finite volume method for mechanical draft counterflow and crossflow tower. For a coupling problem between water and air system, a turbulent two phase flow is considered. The Effectiveness-NTU method is used for modeling of the dry type heat exchanger. The parametric simulations such as the relative flowrate of air and attachment length of an air mixer are performed to examine the effect on plume abatement. It is found that if the relative air flowrate ratio and the adequate air mixer type are chosen well in addition to the ratio of water to air flowrate, the loss of cooling capacity and the additional cost are reduced and the plume is abated.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.11
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• pp.1049-1058
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• 2001

The performance and design analysis for a NWD cooling tower using a combined wet and dry type fill are numerically investigated and compared with the experimental results. The Stoecker's method is applied to the wet section and LMTD or NTU-Effectiveness method to the wet and dry sections. The efficiency ratio of the NWD cooling tower to a wet type crossflow cooling tower is 59.34%. The predicted result shows a good agreement with the experimental data within 1.4% error. Plume abatement is far better with a NWD cooling tower than a counterflow cooling tower. It costs less than a conventional wet/dry tower because the finned exchanger is eliminated. This method also leaves out complexity in structure and Intricacy in operation.

• Plant Journal
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• v.14 no.4
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• pp.33-38
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• 2018

In this study, it was confirmed whether the cooling water bypass ratio of packing for plume abatement matched designed value during winter operation of combined cycle power plant. Designed operating wet bulb temperature of the plume abatement cooling tower with 29 Gcal/h capacity had a range from $13^{\circ}C$ to $-20^{\circ}C$, while its designed bypass ratio was from 0 % to 78%, so that increasing rate of the designed bypass ratio was $2.36%/^{\circ}C$ when the external temperature decreased. When the wet bulb temperature at cooling tower inlet had a range from $7.8^{\circ}C$ to $-11.8^{\circ}C$ in a normal operation, it was measured that actual bypass ratio of packing for plume abatement had a range from 23.8 % to 74.3%. While increasing rate of the actual bypass ratio was $2.71%/^{\circ}C$ in a range from $7.8^{\circ}C$ to $-9.55^{\circ}C$, it was $1.61%/^{\circ}C$ under $-10^{\circ}C$ in cold weather condition according to atmospheric temperature drop, therefore it was confirmed that the increasing rate of the bypass ratio for packing was lowered than its design.