• 대한설비공학회지:설비저널
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• 제31권1호
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• pp.36-45
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• 2002

• 대한설비공학회지:설비저널
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• 제23권2호
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• pp.115-122
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• 1994

• 설비공학논문집
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• 제11권5호
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• pp.598-604
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• 1999

The thermal performance of cooling towers is affected by the temperature of inlet water, wet bulb temperature of entering air add water-air flow rate. In this study, the effects of these variables are simulated using NTU-method and experimentally investigated for the counter-flow cooling towers. The simulation program to evaluate these variables which affect the performance of cooling tower was developed. The maximum errors between the results of simulations and experiments were 3.8% under the standard design conditions and 5.4% under the other conditions. The performance was increased up to 46~50% as the water loading was increased from $6.8m^3$/$hr\cdot m^2$ to $15.9m^3$/$hr\cdot m^2$. The range was reduced up to 56~42% when the wet bulb temperature of the entering air was increased from $22^{\circ}C\; to\; 29^{\circ}C.$

• ESCO지
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• 통권53호
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• pp.62-69
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• 2008

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.1096-1101
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• 2005

In this study, the experiment of thermal performance about closed-type hybrid cooling tower was conducted. A closed type cooling tower is a device similar to a general cooling tower, but with cooling tower replaced by a heat exchanger. The test section for this experiment has the process that the cooling water flows from top part of heat exchanger to bottom side in the inner side of tube, and spray water flows gravitational direction in the outer side of it. Air contacts of tube outer side are counterflow. The heat transfer pipe used in this experiment is a bare type tube having an outside diameter of 15.88mm. In this experiment, heat performances of the cooling tower are calculated such as overall heat transfer coefficient of between the process fluid and air, cooing capacity and pressure drop.

• 동력기계공학회지
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• 제9권2호
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• pp.93-98
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• 2005

The performance of cooling tower is dependent on the thermal performance of the packings. It's assessed by heat transfer rate and fan power. In this study, new packing was developed for application in compact type cross-flow cooling tower. The packing characteristic curve and the pressure drop curve were obtained by measuring packing characteristic values and pressure drops of small sized filler in comparison to existing mid-large sized filler. The heat transfer characteristics on small sized filler are about 66% higher than existing mid-large sized filler. The pressure drop characteristics on small sized filler are about two times of the pressure drop characteristics on existing mid-large sized filler.

• 설비공학논문집
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• 제15권12호
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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.

• Journal of Advanced Marine Engineering and Technology
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• 제32권4호
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• pp.528-533
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• 2008

A closed circuit cooling tower having high temperature of cooling water and small water flow rate is investigated. To study the characteristics of the heat transfer of heat exchanges in a cooling tower with multi paths a numerical method is used. The results show that the staggered tube arrangements in a bank show better performance than aligned ones for temperature variation with various outer diameters of tube bundles. In case of one pass, the 15.88 mm tube case shows about 9% better performance than the 25.4 mm tube case. In two paths, the tube outside diameter of 15.88 mm show about 14.4% better results than the 25.4 mm diameter case.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2322-2327
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• 2008

This paper is to provide analysis model that can be used to investigate the improvement in energy efficiency for cooling tower by using fresh air. Numerical analysis of Air-cooled heat exchanger for single-phase flow with variations of outdoor air temperature has been performed. A complete set of correlations of the heat transfer in both refrigerant and air sides was employed for predicting the heat transfer rate. The numerical results derived from the correlations were verified with experimental results. The energy consumption for a hybrid cooling tower has been compared for variation of a outdoor air temperature. The results showed that the hybrid cooling tower in low outdoor temperature offers a significant improvement in energy efficiency. The thermal analysis aids significantly in the solution of the design problem of hybrid cooling tower.

• 설비공학논문집
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• 제13권11호
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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.