Natural Draft Dry Cooling Tower Research Articles

Air Equalizing Mechanism in Cooling Performance Improvement of Vertical Delta-Type Radiators

Based on the design and measured data of one actual tower, a three-dimensional numerical model for a natural draft dry cooling tower (NDDCT) was created and validated under constant heat load. This enabled the performance improvement mechanism of air equalizing on vertical delta-type radiators (VDRs) to be clarified by detailed analysis of key parameters, such as the exit water temperature, heat transfer coefficient, and mass airflow. Under the impact of typical ambient crosswind, all VDRs were retrofitted with air-side-equalizing devices. It was found that the exit water temperatures of the whole NDDCT decreased by 0.865 °C, 0.593 °C and 0.186 °C under the studied ambient crosswind speeds of 2.5 m/s, 4 m/s and 12 m/s, respectively. The performance improvement mechanism of air-side equalizing was investigated for three VDRs, which were located on the upwind, tower lateral, and downwind sides under crosswind impacts. Besides the studied VDRs, the performance of the neighboring VDRs behind them was also improved by the optimized aerodynamic field and the reduced hot wind recirculation around them. In addition, the average heat transfer coefficients of the VDRs were enhanced, which could lay the foundation for improving the cooling performance of thermodynamic devices with VDRs.

Effect mechanism of cooling delta aerodynamic field equalizing on the cooling characteristics of dry cooling tower

As the key heat transfer components for large-scale natural draft dry cooling tower (NDDCT), the cooling deltas perform poorly when subjected to ambient crosswinds, thus leading to the cooling performance degradation of NDDCT. To enhance the cooling delta's heat transfer capabilities, the effect mechanisms of aerodynamic field equalizing, i.e. air equalizing, on the deltas were studied by the validated three-dimensional (3D) numerical model. For the deltas arranged around NDDCT, the aerodynamic fields, the air flow rates, and the water temperature were all analyzed for cooling columns composing deltas. By comparing the two situations with air equalizing or without in the midst of cooling delta, it could find that the air equalizing diminished the air flow rate differences between the two columns in one delta, which improved the cooling characteristics of the poorer-performing columns mostly at the delta's leeward but deteriorated those of the better-performing columns mostly at the delta's windward. With the air equalizing, the cooling characteristics of the two columns in one delta were balanced. And then the cooling characteristics of most deltas and the whole NDDCT were improved to some extent at varying crosswind speeds, which was significant for the design optimization of conventional delta-type radiators.

The Effect of Wind Direction on the Cooling Capacity of Short Dry Natural Draft Cooling Towers Operating in Close Proximity

Abstract The layout of multiple natural draft dry cooling towers could have a significant influence on the performance of the cooling system in concentrated solar power (CSP) plants; however, this has never been quantified. Hence, this work used computational fluid dynamics (CFD) modeling to analyze the cooling capacity of two short natural draft dry cooling towers (NDDCTs) on a common site for a range of tower spacings, wind-speeds, and wind incidence angles. The results show that the cooling performance of the towers is a strong function of tower spacing and their orientation with respect to the wind direction. It was found that when the wind came at a 90-deg wind incidence angle (i.e., normal to a line drawn between the two towers), their cooling capacity was improved at tower spacings of less than 1.8 tower diameters (1.8D), though for the other tower spacings, there was no interaction between the towers. However, with the wind at 45 deg to the towers, the flow around the towers resulted in a decrease in their cooling capacity at tower spacings of 1.8D and 2.6D. Most interestingly, it was found that orienting the towers in line with the prevailing wind direction delivered improvements in the cooling capacity of up to 30%. This is due to the windward tower acting as a passive windbreak. Hence, as CSP plant capacity is increased, and additional cooling towers are required, these should be placed close to any existing tower and oriented along the line of the prevailing winds.

Investigation on the spray strategy for the inlet air pre-cooling of natural draft dry cooling tower under typical crosswind

Spray pre-cooling technology is an effective way to promote the thermal performance of natural draft dry cooling tower (NDDCT) during high temperature periods. This paper aims to explore the spray strategy of different nozzle arrangements with low water consumption on the thermal performance of NDDCT under typical crosswind of 4 m/s, which is the most frequent wind speed. A 3-D model of a 120 m high NDDCT pre-cooled with nozzle spray was developed using Fluent 16.2. Half of the NDDCT model was simulated due to its symmetry structure. Four cases of spray strategies to incompletely saturate the tower airflow and three cases of spray strategies to fully saturate the tower airflow were extensively studied. The results show that: (1) the seven spray strategies to incompletely/fully saturate the tower airflow all improve the thermal performance of the NDDCT; (2) the heat rejection rate of the half NDDCT by case 8 is the highest as 73.32 MW while the heat rejection increment per unit water flowrate by case 3 is the highest as 1.39 MJ/kgw. The trade-off between the performance improvement of the NDDCT and water consumption should be considered during the design of the spray pre-cooled NDDCT under crosswind.

Numerical investigations on the start-up of a dual-tower system under crosswind: Collaborative and competitive effects

A three-dimensional numerical model is established to investigate the start-up process of a dual-tower system composed by two natural draft dry cooling towers (NDDCTs) under crosswind from 1 to 10 m/s. The coupled effects of tower spacings (1.5D, 2D and 3D) and incidence angles (0°, 45° and 90°) on the transients of the dual-tower system are checked. A simplified analysis identifies an enhancing factor EN and an impairing factor IM, which mutually determine the start-up duration of the dual-tower system. The numerical results present a general trend of the start-up process for a dual-tower system, i.e., it increases under mild crosswind from 1 to 4 m/s, peaks between 4 and 5 m/s and drops from 5 to 10 m/s. However, the dual-tower system at different tower spacings interacts with crosswind of different incidence angles in different ways during the start-up process. When paralleling with crosswind at 0°, both NDDCTs collaborate via the rising plumes. The collaborative effect accelerates the start-up process and is enhanced at a closer tower spacing. While perpendicular to the crosswind at 90°, both NDDCTs compete for the bottom inlet air via the shared zone. The competitive effect extends the start-up duration but is weakened at a larger tower spacing. While both effects exist simultaneously at a 45° wind incidence angle, leading to an increase of duration from 1.5D to 2D as the collaboration is weakened more, but a decrease of duration from 2D to 3D as the competition is decreased more. These conclusions will be useful for the request of larger cooling capacity and dispatchability on power blocks in hybrid energy systems.

Nozzle arrangement study for pre-cooling the inlet air of natural draft dry cooling tower under crosswinds

Crosswind affects the airflow fields of the natural draft dry cooling towers (NDDCTs), thus the spray zones for pre-cooling the inlet air of the NDDCT might be different from no crosswind. Therefore, a 3-D model of pre-cooled NDDCT under crosswind was established by Fluent 16.2 to investigate the feasible zone of nozzle spray of a 120 m high NDDCT based on the behavior of the droplets. Six nozzle heights, nine nozzle radiuses and four spray angles were simulated for the NDDCT application within the crosswind speeds of 0∼10 m/s. The evaporation percentage of droplets higher than 99% and the maximum effective evaporation ratio are selected as the criterion for the feasible zone of nozzle arrangement. Simulation finds that: (1) the nozzle arrangement height should be set at 7 m when the crosswind speed is 0 m/s, and it should be set at 9 m when the crosswind speeds are 2 m/s, 4 m/s,6 m/s, 8 m/s and 10 m/s, respectively. (2) The feasible spray angles of nozzles are 0°and 90° at the crosswind speeds of 0∼4 m/s and 6∼10 m/s, respectively. (3) The nozzle radiuses are 0∼41.5 m at crosswind speed of 0 m/s, they are 0∼21.5 m at the crosswind speed of 2 m/s, and they are 0∼16.5 m when the crosswind speeds are 4 m/s, 6 m/s, 8 m/s and 10 m/s, respectively based on the above feasible heights and spray angles. The results will provide a guidance for nozzle design of spray pre-cooled NDDCT under crosswinds.

Optimization of the circulating cooling water mass flow in indirect dry cooling system of thermal power unit using artificial neural network based on genetic algorithm

The power consumption of circulating pumps can be effectively reduced by optimizing the circulating cooling water mass flow rate in indirect dry cooling system of a thermal power unit. The coupling algorithm of the artificial neural network optimized by genetic algorithm and the heat transfer model of the condenser and the air-cooled heat exchanger was established to obtain the air mass flow rate into the natural draft dry cooling tower (NDDCT). Assuming that the steam turbine back pressure is constant, the optimal mass flow rate of the circulating cooling water corresponding to the ambient temperature and the ambient temperature range in which the mass flow rate can be adjusted were obtained when the output power load was constant by using the heat transfer model of the condenser and the air-cooled heat exchanger. Calculation results show that the optimal mass flow rate of the circulating cooling water corresponding to ambient temperature gradually increased with the increase in the output power load and the decrease in the minimum inlet temperature of circulating cooling water in the NDDCT. Moreover, the ambient temperature range in which the mass flow rate of the circulating cooling water can be adjusted gradually decreased. Meanwhile, the ambient temperature range gradually decreased with the increase in the minimum outlet temperature of the circulating cooling water in the NDDCT, but the optimal mass flow rate corresponding to the ambient temperature remained unchanged. Taking the operating state of the unit on a certain day as an example, at least 16,515 kWh circulating pump power consumption can be saved by adjusting the circulating cooling water mass flow rate to the optimum value.

Spray Effect on the Thermal Performances of a Dry Cooling Tower

Pre-cooling the inlet air of a dry cooling tower by means of a spray can improve the tower performance during periods of high temperature. To study the spray effect on the thermal performance of natural draft dry cooling towers (NDDCTs), in this study 3-D numerical simulations of such a process have been conducted using Fluent 16.2 (a two-way coupled Eulerian-Lagrangian approach). The considered NDDCT is 120 m high and only half system is simulated due to its structural symmetry. Three different spray strategies have been investigated at a typical crosswind speed of 4 m/s, which is the most frequent wind speed. The results have shown that: (1) The three implemented spray strategies can improve the thermal performance of the studied NDDCT with a varying degree of success. In one case, the heat rejection rate can be increased by 35.2%, and the tower outlet water temperature can be decreased by 2.1°C when compared with the no spray case; (2) To improve the thermal performance of the NDDCT using a small amount of water, the design of the spray pre-cooling system must include more nozzles on the windward and fewer or even no nozzles on the leeward sides of the NDDCT.

Investigation on the control mechanism of spray pre-cooling the inlet air of natural draft dry cooling tower

• A 3-D model of spray pre-cooled NDDCT was developed. • The control mechanism of nozzle spray was investigated from three aspects. • The highest modified cooling efficiency of 73.2% occurs in spray scheme 18. • The heat rejection rate of the NDDCT increases from 123.67 MW to 176.08 MW. • The regional regulation principle of spray water flowrate is proposed. Spray pre-cooling the inlet air can improve the thermal performance of natural draft dry cooling towers (NDDCTs). To achieve the purpose of good performance improvement with minor water consumption, it is necessary to investigate the control mechanism of spray pre-cooling system for NDDCT performance improvement. This paper developed a 3-D model of spray pre-cooled NDDCT using Fluent 16.2. The NDDCT was 120 m high and 1/12 NDDCT was simulated due to the symmetry. The control mechanism of nozzle spray was investigated from three aspects, i.e., the spray angles, arrangement of nozzles, and spray water flowrates. Simulation finds that: (1) To achieve the goal of maximal cooling performance improvement with benchmark spray water flowrate, the recommended scheme is 18, which consists of 1 upward nozzle at height of 3 m, 3 co-flow nozzles at height of 5 m, 3 nozzles with the spray angle of 45° at height of 5 m, 3 upward nozzles at height of 8 m, 3 nozzles with the spray angle of 45° at height of 11 m and 3 nozzles with the spray angle of 45° at height of 13 m. The heat rejection rate of the whole cooling tower increases from 123.67 MW to 176.08 MW because the natural convection is enhanced; (2) The highest modified cooling efficiency at the heat exchanger surface is 65.0 % when the spray water flowrate reduced to 75 % of benchmark spray water flowrate while it is 47.1 % with 50 % of benchmark spray water flowrate; (3) To achieve more uniform cooling, it is suggested that the nozzles should be arranged at the tower inner region in low-height zone while the nozzles should be arranged at the tower outer region in high-height zone. Besides, large spray water flowrate at high-height zone is recommended to achieve maximal cooling effect with low water consumption.

The effect of crosswind and installation of wind-break deflector on the performance of natural draft dry cooling tower (NDDCT)

Natural draft dry cooling tower (NDDCT) is one of the most important components of combined power plant cycles in arid regions. Studies illustrate that being subjected to the wind blowing has negative effects on NDDCT's thermal performance. These adverse effects mostly inflict on the outlet port of the tower and the installation platform of the radiators at the bottom of the tower. In this study, the influence of installing wind-break deflectors at the outlet port of the tower and addressing the negative impacts of the wind is investigated. Considering the buoyancy effect for a 3-D incompressible flow, the flow field inside and outside the tower as well as the heat transfer from the radiators is modeled through simultaneously solving the Navier-Stokes and energy equations via computational fluid dynamics method (CFD). The performance of NDDCT is compared with and without the presence of deflectors where considered variables are height of the deflector and wind velocity. The improvement in the rate of the heat released to the atmosphere from the radiators will be estimated. Generally, in the presence of deflector walls the thermal performance of the tower enhances. With the increase in the height of deflectors, the thermal performance will further improve. For instance, the enhancement in the tower's performance with a 12-m deflector at wind velocities of 5 and 20 m/s is 57 and 44 percent, respectively.

Coupled CFD and 3E (Energy, Exergy and Economical) analysis of using windbreak walls in heller type cooling towers

Generally, Montazer Ghaem Combined Cycle Power Plant (MGCCPP) is equipped with natural draft dry cooling towers (NDDCT) and its performance strongly depends on environmental conditions such as wind speed. Thus, the present study aims to evaluate the effects of wind blowing on the cooling towers (CTs) efficiency and propose methods to improve their performance. It can help increase plant efficiency and decrease energy loss, which leads to cleaner production. For this purpose, the cycle of MGCCPP is modeled simultaneously using CFD and energy-exergy analyses for the first time. Moreover, the effect of windbreak walls (WBWs) on CT performance and CCPP are addressed. The results of CFD analyses are used to recognize the behavior of the towers in different wind speeds and deriving heat rejection. Based on obtained results, using the WBW in the prevailing wind leads to about 6.5 MW excess power in each unit. According to the economic analysis, the payback period of the three proposed plans is 14, 15.5, and 16 months, which is fully justified.

Improvement mechanism of wedged column on the cooling performance of vertical delta radiator

Vertical delta radiators were widely used in dry cooling towers as the key radiator element. But the delta structure was very easy to induce large vortex between its two sides when the air was slantly flow in, which was very commonly under real natural crosswind conditions. To alleviate the adverse effect of large vortex on its adjacent cooling column radiator, one type of wedged cooling column was proposed, which was a columnar cooling tube bundle with a wedged-shaped gap. A three-dimensional (3D) numerical model for natural draft dry cooling tower (NDDCT) with vertical delta radiators was established and validated to study the improvement mechanism of wedged cooling column on the cooling performance of vertical delta radiators. Both aerodynamic field and air temperature field were compared and studied between the vertical delta radiators with wedged columns (VDRWs) and usual vertical delta radiators. It could be found that both the heat transfer temperature difference and air mass flow rate of VDRWs were greater than those usual, which could decrease the exit water temperature by 0.27 and 2.23 °C separately at no crosswind and 7 m/s crosswind. Beside, the equivalent outlet water temperature TA could decrease by 0.493 °C, which suggested that the wedged cooling column could improve the cooling performance of vertical delta radiators to some extent.

Comparison on cooling performance of pre-cooled natural draft dry cooling towers using nozzles spray and wet medium

Evaporative pre-cooling technology improves the cooling performance of natural draft dry cooling towers (NDDCTs) by introducing a certain amount of water into the air entrance. This paper compares the effects of different evaporative pre-cooling systems (i.e., normal wet-medium arrangement, A-frame wet-medium arrangement and nozzle spray) on the cooling performance of a 167 m high NDDCT. Based on the meteorological data of Naomao lake in Xinjiang in 2015, two MATLAB programs were developed for case studies. This study finds all the evaporative pre-cooling systems can improve the NDDCT's cooling performance in high temperature period. In non-high temperature period, the NDDCT's performance improvement is unremarkable, and the NDDCT's cooling performance even deteriorates in the case of evaporative pre-cooling using wet medium. In the hottest month of July, the water outlet temperatures of the NDDCT pre-cooled with normal wet-medium arrangement, A-frame wet-medium arrangement and nozzle spray drop 3.2 K, 3.5 K and 3.3 K, respectively when compared with no pre-cooling counterpart. The annual average water consumption values are 39.0 kg/s, 56.4 kg/s and 124.1 kg/s, respectively. Considering all the year around performance improvement, it is suggested to use nozzle spray pre-cooling system while intermittent operation or certain-time period operation should be considered to save water.

Direct Air Capture via Natural Draft Dry Cooling Tower

Capturing carbon dioxide (CO2) from atmospheric air has a great potential to reduce the greenhouse effect, which is of significance to the global campaign against climate change. Due to the extremely low concentration of CO2 in the air, the current carbon absorption technology has the problems of high consumption of both electrical energy to lead the airflow and water evaporation. In this study, a novel direct air capture (DAC) system, which integrates the conventional natural draft dry cooling towers (NDDCTs) and the current DAC technology, is proposed to lower the operating cost during the CO2 capture process and enhance the cooling effects of NDDCTs in a thermal power plant as well. The results indicate that the water evaporation during the CO2 absorption process could create a considerable cooling capacity, which is expected to favor the NDDCTs to reject more heat. Under the design ambient conditions for the NDDCT (30 °C, RH=40%), the thermal performance of the cooling tower can be increased by about 16% with the integration of the DAC absorption process. For a 20 m short NDDCT, the annual CO2 capture capacity is about 846 tons. By using the cost-free natural draft effect provided by NDDCTs, a great amount of electrical energy can be saved. The mutual benefits could be achieved by integrating both systems.

Exploratory research on annular-arranged moist media to improve cooling capacity of natural draft dry cooling tower and thermo-flow characteristics of its radiators

The well-arranged moist media should be a promising solution to improve the thermal performance of the natural draft dry cooling tower (NDDCT) by the synchronous implementations of air inflow field optimization and inflow air pre-cooling. In the present study, a 3D numerical model coupling a full-scale NDDCT and annular-arranged moist media was established, and the effects of the introduced moist media were explored by numerical simulation. Results show that the moist media are effective to increase the cooling capacity of the NDDCT under crosswind, with the maximum increment of 20.9% achieved at the medium wind speed of 8 m/s. The cooling capacity of the tower after the action of the moist media under the wind speed of 4 m/s exceeds the original maximum one. Through air inflow field optimization provided by the media, thermo-flow characteristics of the delta-form radiators improve. Performance deviation among the radiators alleviates, and the two cooling columns of each radiator almost have identical performance. With the further implementation of inflow air pre-cooling, each radiator, especially its cooling column right downstream the medium, obtains a further performance improvement. Under crosswind, inflow air pre-cooling is generally superior to air inflow field optimization on promoting tower performance, but the opposite result is achieved at the wind speed near 8 m/s. From the view of cost-effectiveness, the introduced moist media are most efficient at the wind speed of 6 m/s, and a 1.50 MW increment in the cooling capacity of the tower can be achieved by every 1 kg/s water evaporation.

A general mathematical model for predicting the thermal performance of natural draft dry cooling towers and extending it to three aligned towers

ABSTRACT Natural draft dry cooling towers (NDDCTs) are the most important cooling components in steam power plants in regions with lack of water. Thermal performance of these cooling towers is highly affected by the ambient temperature and wind velocity. There have been several studies in the last few decades to estimate or measure the performance of such towers in different ambient conditions. In this study, the thermal performance of four different NDDCTs (with an only similar parameter of tower’s outlet diameter to height ratio (D/H) of around 0.5) under various ambient conditions is investigated using a recently proposed theoretical method. Results showed that the towers behave in the same way under different ambient conditions. Having a reference condition and calculating three coefficients, a simple general mathematical model is created that can predict the tower’s thermal performance for a wide range of applicable wind velocities. It is shown that the selection of the reference condition has a high effect on the error generated by the model. The range of the best reference condition for using the mathematical model is obtained to be wind velocities between 3 and 4 m/s and initial temperature difference (ITD) of more than 20°C. The proposed model is validated against other reported NDDCTs (numerical models for 0.41 < D/H < 0.63). The maximum error in heat rejection was shown to be 13%. This mathematical model is also extended to predict the performance of a three aligned NDDCTs located in Shiraz/Iran, by introducing a correction factor.

Impact of tower spacing on the performance of multiple short natural draft dry cooling towers for calm conditions

Natural draft dry cooling towers (NDDCTs) serve a fundamental role in the deployment of concentrating solar power (CSP) plants. In a multi-tower cooling system, there is a need to be able to position them correctly so that their performance as a group is maximised. To do this, an understanding of the effect they have on one another is needed. Hence, this work investigated the effect of tower spacing on the performance of multiple cooling towers under calm conditions using computational fluid dynamics (CFD) simulations. The applied CFD methods were validated by comparing the current results with real cooling tower results. It found that towers in close proximity would compete for air at their inlet, resulting in distorted velocity and temperature distributions at the radiator surface. Furthermore, the results show that at a tower spacing of less than two tower diameters (2 D) where D is the diameter of the tower, a reduction in the scavenging area between the towers limits the air supply to the towers and this interaction decreases the cooling performance of the towers. The results of three NDDCTs showed that the heat rejection of the middle tower which is surrounded by two towers is highly influenced by the tower spacing and at very low tower spacings, the heat rejection decreases by up to 15%. This new finding holds particular design significance if multiple NDDCTs are deployed on CSP sites that experience a high frequency of calm (no-wind) conditions.

A numerical study on interactions between three short natural draft dry cooling towers In an in-line arrangement

Natural draft dry cooling tower (NDDCT) are a favourable choice for the cooling system of concentrating solar thermal power (CST) plants located in arid regions with high solar radiation. However, additional cooling towers may be required as the capacity of the CST plants is increased. The geometrical arrangement of the NDDCTs is an influencing parameter on the thermo-flow performance of the entire system. The aim of this study was to investigate the effect of tower spacing and wind speed on the performance of three short NDDCTs in an in-line layout. The simulated tower is representative of an actual steel-membrane cooling tower in a campus of the University of Queensland. The geometry of the cooling tower in this study is a cylindrical shape with a horizontally arranged air-cooled heat exchanger, and is 20 m high with a diameter of 12.5 m. This study investigated the effect of two major parameters: wind speeds (0–8 m/s), wind and tower spacings (1.8D, 2.6D, and 4.2D) on the thermo-flow performance of the cooling towers. The interaction of the towers from the bottom and top of the towers were identified at different tower spacings and wind speeds. At all tower spacings, the windward tower protects the middle and leeward towers by deflecting the upcoming wind. The interaction of the towers happens both from the bottom and top of the towers. Finally, it was concluded that enlarging the towers increase the thermal performance of the towers during windy conditions and this may lead in better protection of the windward tower for the leeward ones.

Theoretical and numerical investigations of swirl enhanced short natural draft dry cooling towers

A new draft equation involving swirling motions for natural draft dry cooling towers (NDDCTs) is derived and solved analytically. A 2-D axisymmetric model for a short NDDCT is built and computational fluid dynamics (CFD) simulations are carried out to verify the theoretical predictions. Results show that the optimized location for swirl input is at the tower outlet to avoid the swirl decay. It is noted that the swirl influence on the air flow draft velocity gradually becomes significant especially when the dimensionless input swirl ratio exceeds 2. The theoretical predictions generally agree with the numerical results, but deviate when: (1) vortices adjacent to the wall occur in the presence of excessively strong swirl, in the case with swirl created by a thin source zone; (2) cold air inflow penetrates due to the significant heat exchanger resistance coefficient; (3) vortex breakdown appears, in the case with swirl filling the whole tower. All the aforementioned unfavourable phenomena are local effects and thus cannot be predicted by the draft equation unless proper local resistance terms are added.

A novel method integrating windbreak walls with water distribution to mitigate the crosswind effects on natural draft dry cooling towers

This paper proposed a novel method combining both air side optimization (windbreak walls) and water side optimization (water distribution) to reverse the side effects of crosswind on natural draft dry cooling towers (NDDCTs). A three dimensional (3-D) numerical model of a 20 ​m NDDCT based on the University of Queensland NDDCT Gatton test rig is developed. Windbreak walls, designed at three different attack angles towards wind direction (α ​= ​0°, 30° and 60°), could generate an extra amount of the cooling capacity especially at high crosswind speeds, but the contribution is sensitive to the wind attack angles. While water distribution to improve the cooling performance of Gatton NDDCT is not as good as that brought by windbreak walls. However, water distribution could make use of the non-uniform air flow distribution caused by windbreak walls, exploring much more cooling capacity under windy conditions, therefore. With the favor of water distribution, the cooling performance of Gatton NDDCT with walls could be further lifted by 1.37%, 3.24%, 5.75%, 9.66%, 13.07% and 16.06%, respectively from vcw ​= ​3 ​m/s to 8 ​m/s. In summary, the cooling performance of Gatton NDDCT can be lifted beyond or almost maintained at the designed value under all crosswind speeds and wind attack angles.