Water spray for pre-cooling of inlet air for Natural Draft Dry Cooling Towers – Experimental study

Alkhedhair, Abdullah M.; Guan, Zhiqiang; Jahn, Ingo; Gurgenci, Hal; He, Suoying

doi:10.1016/j.ijthermalsci.2014.11.029

Cited by 58 publications

(42 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although CFD simulation for water spray performance is a powerful tool, it is a challenging task with respect to spray initialization in Lagrangian modeling approaches [114]. The performance of spray cooling systems is sensitive to initial injection parameters [20,115]. Various numerical investigations showed the importance of accurate representation of the nozzle initial characteristics in the simulation [83].…”

Section: Chapter Summarymentioning

confidence: 99%

“…The performance of spray cooling systems involving particle spray is determined by their initial injection parameters [20,115]. Various numerical investigations showed the importance of the accuracy of the representation of the nozzle initial characteristics in the simulation in order to be validated with the experiments [83].…”

Section: Nozzle Representationmentioning

confidence: 99%

“…The test section side walls are made of transparent acrylic to allow visualization of the water spray as well as giving access to the PDPA system and the photographing system. Full detail of the test rig can be found on these studies [115,124].…”

Section: Test Sectionmentioning

confidence: 99%

“…The laser system consisted of 600 mW argon-ion lasers (532, 561 nm wavelength). Optical setup and run settings of the PDPA system can be found in Alkhedhair et al [115]. A 2-Axis Traverse System was used to move the PDPA system during the experiment.…”

Section: Spray Characterisationmentioning

confidence: 99%

“…A series of wind tunnel experiments have been conducted in a previous study [115] for spray characterisation of nine promising high pressure, hollow-cone nozzles for inlet air pre-cooling at different atomization pressures and environmental conditions. Hollow-cone nozzle is found to be the best option for spray cooling systems and is widely used in humidifying applications [46].…”

Section: Experimental Observationsmentioning

confidence: 99%

See 4 more Smart Citations

Modelling and experimental study of spray cooling systems for inlet air pre-cooling in natural draft dry cooling towers

Alkhedhair¹

View full text Add to dashboard Cite

Geothermal energy is a promising renewable energy to be used for baseload electricity. Most potential sites with high geothermal temperature are mostly located in remote areas where water is limited. This is besides water scarcity and environmental protection, which made dry cooling systems a better alternative solution for heat rejection of power plants. Furthermore, natural draft cooling towers have the advantage of avoiding parasitic losses introduced by the fans at mechanical draft cooling towers. However, power plants utilizing dry cooling technologies experience a significant reduction in power generation during high ambient temperature periods. This reduction often goes along with the peak power demand which results in a great loss for the power plant owners. In certain instances, dry cooling tower performance can be enhanced during these periods by pre cooling of the inlet air by spraying atomized water into the inlet air.The present study introduces the use of spray cooling for inlet air pre-cooling in natural draft cooling towers. Spray cooling is investigated in this study due to its simplicity, low capital cost, ease of operation and maintenance, and capability of increasing power plant efficiency while consuming only a small amount of water compared to wet cooling towers or other evaporative cooling methods. Although spray cooling has found successful applications in process coolers and gas turbine inlet air cooling, the large scale applications in power industry have been limited.Several issues limit the application in power industry. The main one is the incomplete evaporation of water droplets which can cause corrosion and scaling of heat exchanger surface. Incomplete evaporation also increases operational cost due to water consumption. To the best of our knowledge, a detailed investigation of the spray cooling performance in natural draft dry cooling towers operating environment has not yet been performed. The aim of the current work is to optimise a spray cooling system for inlet air pre-cooling in natural draft dry cooling towers.In the present study, an Eulerian-Lagrangian 3-D numerical model was developed which is capable of simulating evaporating water sprays produced by real nozzles. In order to reproduce real nozzle characteristics in the simulation, a new adaptable method for hollow-cone spray representation in Eulerian-Lagrangian numerical models was developed. This allows real nozzles characterised during experiments to be included in the simulation, thereby correctly accounting for radial evolution of droplet size distribution and air/droplets momentum exchange. The CFD model was applied to calculate local droplet transport and evaporation, and spray cooling efficiency at different operating conditions for spray cooling systems optimisation under typical Natural Draft Dry Cooling Tower conditions.iii Experimental measurements from a wind tunnel test rig simulating Natural Draft Dry Cooling Tower inlet flow conditions have been performed in order to investigate droplet transport...

show abstract

Section: Chapter Summarymentioning

confidence: 99%

Section: Nozzle Representationmentioning

confidence: 99%

Section: Test Sectionmentioning

confidence: 99%

Section: Spray Characterisationmentioning

confidence: 99%

Section: Experimental Observationsmentioning

confidence: 99%

See 3 more Smart Citations

Modelling and experimental study of spray cooling systems for inlet air pre-cooling in natural draft dry cooling towers

Alkhedhair¹

View full text Add to dashboard Cite

show abstract

Analysis of the performance of direct contact heat exchange systems for application in mine waste heat recovery

Kalantari

Amiri

Ghoreishi‐Madiseh

2021

Intl J of Energy Research

View full text Add to dashboard Cite

Due to their relatively high thermal effectiveness and ease-of-use, direct contact heat exchange units are a favorable choice in heat recovery applications. Today, spray-based direct heat exchangers are commonly used for a variety of applications, including evaporative cooling and heat recovery. Yet in spite of their versatility, these heat exchangers are not well-understood, mainly due to their complex liquid/gas interactions, which may deem poorly-designed systems as undesirable and infeasible. Spray nozzle height and type (hollow and full cone), droplet diameter distribution, inlet air velocity and humidity, and water spray velocity are key parameters required to establish a clear understanding of direct heat exchange performance. To better understand such a multivariable phenomenon, this article offers a comprehensive study of the impact of these key factors. The main purpose of this study is to evaluate the validity of two different methods proposed for evaluating the performance of heat and mass transfer in large-scale direct contact heat exchangers, namely one-dimensional and threedimensional approaches. The results of the present study show that while the one-dimensional approach is able to capture the experimental data within 10% of agreement with experiment, the three-dimensional approach reduces this error to 5%. In addition, this study aims to provide a framework to conduct future parametric studies with the goal of highlighting key performance factors understanding of which are a necessity for improved design of direct contact heat exchangers used in mine waste heat recovery applications.

show abstract

Selective Design of an Experiment for Evaluating Air–Water Hybrid Steam Condenser for Concentrated Solar Power

Dirbude

Khalifa

Chandra

2017

Springer Proceedings in Energy

View full text Add to dashboard Cite

Water spray for pre-cooling of inlet air for Natural Draft Dry Cooling Towers – Experimental study

Cited by 58 publications

References 8 publications

Modelling and experimental study of spray cooling systems for inlet air pre-cooling in natural draft dry cooling towers

Modelling and experimental study of spray cooling systems for inlet air pre-cooling in natural draft dry cooling towers

Analysis of the performance of direct contact heat exchange systems for application in mine waste heat recovery

Selective Design of an Experiment for Evaluating Air–Water Hybrid Steam Condenser for Concentrated Solar Power

Contact Info

Product

Resources

About