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THREE-DIMENSIONAL REGULARITIES OF DISTRIBUTION OF AIR-INLET CHARACTERISTIC VELOCITY IN NATURAL-DRAFT WET cooling tower

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Journal of Hydrodynamics 2008年第3期20卷 323-330页

作者： WANG Kai SUN Feng-zhong ZHAO Yuan-bin GAO Ming SHI Yue-tao School of Energy and Power Engineering Shandong University Jinan 250061 China

A model for heat and mass transfer in a natural-draft wet cooling tower was established. Numerical simulation with the κ-ε turbulent model was conducted. Distribution rules of air inlet aerodynamic field were studied. Field experiments were done in a cooling tower in power plant, and the test data was compared with the related results. The definition of characteristic air velocity was proposed and its influencing factors, such as the cross-wind velocity and circumferential angle, were quantitatively studied. It can be used to evaluate the performance of cooling tower and to calculate the ventilation quantity and resistance of air inlet. It is also a theoretical basis for cooling tower design and performance optimization.

关键词： cooling tower flow field numerical simulation air inlet

Collapse Simulation and Response Assessment of a Large cooling tower Subjected to Strong Earthquake Ground Motions

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 691-715页

作者： Tiancan Huang Hao Zhou Hamid Beiraghi Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou510405China Department of Civil Engineering South China University of TechnologyGuangzhou510641China Department of Civil Engineering Mahdishahr BranchIslamic Azad UniversityMahdi Shahr***Iran

Large cooling towers in thermal power plants and nuclear power plants are likely to suffer from strong earthquakes during service *** resulting destructions of the cooling towers would endanger the power plants and threaten the security of the related *** is important to use effective means to evaluate the safety status of the cooling towers and guide further precautions as well as retrofitting *** paper is therefore focused on an elaborate numerical investigation to the earthquake-induced collapses of a large cooling tower structure.A complete numerical work for simulation of material failure,component fracture,structural buckling and system collapse is presented by integrating the stochastic damage constitutive model of concrete,refined structural element models,and some other key *** results indicate that the damage behavior and collapse mode of the cooling tower are affected notably by the randomness specification of ground *** collapse mechanisms of the cooling tower are studied from the energy absorption and dissipation points of *** effective energy-based criterion is introduced to identify the collapse of the cooling tower under ground motion *** distinct collapse modes are observed,the collapse criterion can predict well the damage and failure of the cooling *** proposed methodology is vital to better understanding the disastrous mechanisms and potential failure paths in optimal design of the cooling towers to ensure safety.

关键词： cooling tower concrete damage mechanics collapse criterion responses

Wind?Induced Interference Effect Between Newly?Built cooling tower and Existing cooling tower

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Transactions of Nanjing University of Aeronautics and Astronautics 2020年第1期37卷 88-98页

作者： DU Lin KE Shitang YANG Jie ZHU Rongkuan GE Yaojun College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China State Key Laboratory of Disaster Prevention Civil Engineering Tongji UniversityShanghai 200092P.R.China

Disturbance effect is one of the important factors for wind damage to large cooling *** studies on the wind-induced interference of cooling tower groups are aimed at the same size and the lack of wind-induced interference effects between cooling towers of different *** the background of the additional cooling tower project at Shandong Luxi Power Plant in China,the rigid body pressure wind tunnel test is carried out to obtain 194 conditions for the three combinations of the existing four-tower combination(small size),the new two-tower combination(large size)and the six-tower combination surface wind pressure *** simulation of the surrounding flow field of the cooling tower group with the most unfavorable interference condition of the six-tower combination is conducted using the computational fluid dynamics(CFD)*** on this,the characteristics of the average and pulsating wind pressure distribution of the cooling tower surface under the six-tower combination are mainly studied,and the load interference coefficients of the large-sized cooling tower and the small-sized cooling tower under the three tower group combinations are *** velocity flow field and vorticity changes around the cooling tower group at unfavorable wind angles are analyzed,and the wind-induced interference mechanism between cooling tower groups of different sizes is mainly *** shows that the interference effect between such cooling tower groups of different sizes is much larger than that of cooling tower groups of the same size,which is specifically manifested as the enhancement effect of small-sized cooling towers and the shielding effect of large-sized cooling *** interference coefficient of large-sized cooling tower groups increases by 28%,and the interference coefficient of small-sized cooling tower groups decreases by 6.4%.The airflow acceleration caused by the pinch effect between small-sized cooling tower groups has an a

关键词： cooling tower wind tunnel test wind-induced interference effect mechanism of action numerical simulation

Soft Sensor Approach for Optimal Operation of cooling tower for Energy Conservation

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Soft Sensor Approach for Optimal Operation of Cooling Tower ...

Control Methods and Operation Strategies for Improving Energy Saving in a Multi-cell Fan Based cooling tower System

第26届中国控制与决策会议

作者： Jian-Guo Wang Qian-Ping Xiao Juan-Juan Wang Shi-Wei Ma Wen-Tao Rao Yong-Jie Zhang School of Mechatronical Engineering and Automation Shanghai UniversityShanghai Key Lab of Power Station Automation Technology Institute of Environment & Resources Baosteel Research Institute

This paper presents a data-driven adaptive soft sensor approach to investigate the performance and optimal operation of cooling tower for energy conservation. To achieve this aim, first, the cooling tower process is characterized by an adaptive soft sensor with nonnegative garrote（NNG） variable selection procedure. Then, based on the statistics result of NNG variable selection, the effect of environment temperature and humidity on the cooling capacity was investigated by principal component analysis（PCA）. At last, the optimal strategy of fan operation mode was presented and the implementation of the optimal strategy was investigated for a cooling tower, which showed that there was large room for energy conservation.

关键词： Nonnegative garrote variable selection soft sensor cooling tower energy conservation

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Control Methods and Operation Strategies for Improving Energ...

WIND TUNNEL SIMULATION OF WIND EFFECT ON A GROUP OF HIGH cooling towerS

“第十届中国钢铁年会”暨“第六届宝钢学术年会”

作者： Tsou Ying Chang Chuncheng Wu Chanwei Jang Shishang New Material Research & Development Dept. China Steel Corporation Office of Energy and Environmental Affair China Steel Corporation Department of Chemical Engineering National Tsing Hua University

In cooling towers,the replacement of traditional single-speed fans with variable-frequency drive（VFD）fans or two-speed fans can achieve significant energy ***,concerns regarding frequent on/off switching and the lack of a well-devised controller discourage the widespread *** this study,a temperature zone setting method is proposed to replace the traditional point setting method of fan *** we also developed a multi-fans control ***,the highest allowed temperature of output water in the process is set as the upper limit of a zone in order to further conserve *** strategies are comprehensively analyzed for a virtual cooling tower that uses operational data from an existing VFD-fan-based cooling tower system in *** results of on-site implementation show energy savings of 38%for a 0.75°C zone without increasing the on/off switching *** proposed strategies were further verified via an on-line field *** proposed methods can be universally and easily applied to any existing cooling tower with significant energy conservation.

关键词： cooling tower variable-frequency drive zone setting control

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Acta Mechanica Sinica 1987年第1期3卷 36-43页

作者： Yan Dachun Li Chenxin (Department of Mechanics,Peking University) 1. Department of Mechanics Peking University Beijing China

Aerodynamic interference between high cooling towers in the atmospheric boundary layer(ABL) and uniform flow has been *** the 1/1000 ABL model set up in the 2.25m low speed windtunnel at Peking University,the similarity condition of the cooling tower in the ABL,the simulation resultsof a single tower and some typical tower groups have been *** showed that the Circum-ferential pressure distributions were consistent between the smooth model tower and the prototype tower,and between the rough model tower and the prototype tower with ribs;the two dimensional characteristics inthe circumferential pressure distribution were also noticeable around the middle 1/3 part of the tower afternondimensionalization by local dynamic *** demonstrate that,in the flow with strong turbul-ence the lift coefficient of the downstream cylinder approaches *** the flow with weak turbulence,thepressure distribution reflects a strong nonsymmetry,and the lift coefficient or stagnation pressure of thedownstream cylinder switches alternately between 1 and 0,where a concentrated vortex rolls up and thensheds toward the front of the downstream cylinder and exerts a decisive influence on the aerodynamicproperties of the downstream cylinder.

关键词： atmospheric boundary layer wind tunnel cooling tower

Updating empirical results of wind loads on cooling towers for turbulence intensity effects

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Journal of Southeast University(English Edition) 2021年第4期37卷 413-420页

作者： Cheng Xiaoxiang School of Civil Engineering Southeast UniversityNanjing 211189China

Variations of wind effects on large cooling towers observed at different turbulence intensities for our previous full-scale measurements might be caused by the inherent uncertainties in our physical ***,the one-way analysis of variance(ANOVA)technique is employed for analyzing the data measured on the prototype Pengcheng cooling *** ANOVA indicates that the variations of full-scale wind effects are basically the effects of turbulence intensity,the empirical results of wind loads on cooling towers obtained by generalizing physical experimental data without considering the turbulence intensity effects are updated using model test results obtained in multiple flow *** empirical fluctuating wind pressure distribution is updated based on the fact that the fluctuating wind pressure coefficient linearly increases with the increase in the turbulence intensity,and the empirical formulae of the spectra and the coherences is updated based on conservative *** of the empirical results and full-scale measurement data suggest that the original empirical results are either too conservative or unsafe for ***,economic efficiency and conservativeness will be balanced if the updated empirical results are employed for the wind engineering design.

关键词： cooling tower empirical formula wind tunnel test full-scale measurement turbulence intensity

A New Water Saving Device of Swirling Flow for cooling towers

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Electricity 2011年第4期22卷 52-57页

作者： Xu Yongjun 1 , E Xuequan, Kan Changzhen Key Laboratory for Hydrodynamics and Ocean Engineering, Institute of Mechanics, Chinese Academy of Sciences Key Laboratory for Hydrodynamics and Ocean Engineering Institute of MechanicsChinese Academy of Sciences

This paper is concerned with water saving for water-loop cooling tower system in power plants. A newly developed water saving device of swirling flow is presented. The key point is that the new water saving device makes the steam swirl up along the device wall rather than engender laminar flow in a corrugated plate. The corrugated plate device can save approximately 10 percent of the total lost water. In contrast to the scale model of corrugated plate water saving device, experimental analyses have demonstrated that the new water saving device of swirling flow is more efficient, with a capacity of saving more than 20 percent of water.

关键词： cooling tower water saving swirling flow power plant

Model free optimization of building cooling water systems with refined action space

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Building Simulation 2023年第4期16卷 615-627页

作者： Qiaofeng Xiong Zhengwei Li Wenxia Cai Zhechao Wang School of Mechanical Engineering Tongji University ShanghaiChina Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji UniversityShanghaiChina

Deep Q Network(DQN)is an efficient model-free optimization method,and has the potential to be used in building cooling water ***,due to the high dimension of actions,this method requires a complex neural ***,both the required number of training samples and the length of convergence period are barriers for real ***,penalty function based exploration may lead to unsafe actions,causing the application of this optimization method even more *** solve these problems,an approach to limit the action space within a safe area is proposed in this *** of all,the action space for cooling towers and pumps are separated into two ***,for each type of equipment,the action space is further divided into safe and unsafe *** a result,the convergence speed is significantly *** with the traditional DQN method in a simulation environment validated by real data,the proposed method is able to save the convergence time by 1 episode(one cooling season).The results in this paper suggest that,the proposed DQN method can achieve a much quicker learning speed without any undesired consequences,and therefore is more suitable to be used in projects without pre-learning stage.

关键词： building cooling water system cooling tower cooling water pump DQN controller convergence speed