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Numerical Simulation of Air-cooling Tower 被引量:1
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作者 Lijuan Hao Huanzhi Li Zhaohu Sun Lige TongThermal Energy Department, Beijing University of Science and Technology, Beijing 100083, China 《Journal of Thermal Science》 SCIE EI CAS CSCD 2003年第3期264-269,共6页
A mathematic model for packed air-cooling tower thermodynamic calculation is set up in this paper on the basis of fundamental heat and mass transfer equations. Based on the Double Film theory, direct equation-solving ... A mathematic model for packed air-cooling tower thermodynamic calculation is set up in this paper on the basis of fundamental heat and mass transfer equations. Based on the Double Film theory, direct equation-solving method is used to simulate air-cooling tower, and variation of parameters is taken to analyze the data and results of the program. 展开更多
关键词 packing air-cooling tower computer simulation mathematic model
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Vibration attenuation performance of wind turbine tower using a prestressed tuned mass damper under seismic excitation
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作者 Lei Zhenbo Liu Gang +1 位作者 Wang Hui Hui Yi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期511-524,共14页
With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly complex.In particular,seismic excitation can create a resonance response and cau... With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly complex.In particular,seismic excitation can create a resonance response and cause excessive vibration of the WTT.To investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this study.First,a mathematical model is established based on structural dynamics under seismic excitation.Then,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning optimization.Next,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal acceleration.Finally,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the PTMD.In addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation. 展开更多
关键词 wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation
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Comparison between seismic analysis of twisting and regular 52-story towers considering soil-structure interaction
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作者 Mohamed Naguib Abouelsaad Mohammed Shaaban +1 位作者 Salah El Bagalaty Mohamed E.El Madawy 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期663-675,共13页
A dynamic analysis of both twisting and regular towers is carried out to determine the results of considering soil-structure interaction(SSI)on high-rise buildings.In addition,the difference between the seismic perfor... A dynamic analysis of both twisting and regular towers is carried out to determine the results of considering soil-structure interaction(SSI)on high-rise buildings.In addition,the difference between the seismic performance of using twisting towers over regular ones is investigated.The twisting tower is a simulation of the Evolution Tower(Moscow).The towers’skeletons consist of RC elements and rest on a reinforced concrete piled-raft foundation.The soil model is considered as multi-layered with the same soil properties as the zone chosen for the analysis(New Mansoura City,Egypt).The only difference between both towers is their shape in elevation.The whole system is modelled and analyzed in a single step as one full 3D model,which is known as the direct approach in SSI.All analyses are carried out using finite-element software(Midas GTS NX).Dynamic output responses due to three records of seismic loads are proposed and presented in some graphs.Based on the results,it is concluded that SSI has a considerable effect on the dynamic response of tall buildings mainly because of the foundation flexibility,as it leads to lengthening the vibration period,increasing the story drift and the base shear for both cases. 展开更多
关键词 soil-structure interaction seismic analysis twisting towers base shear story drift finite element method Midas GTS NX
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Research on Transmission Line Tower Tilting and Foundation State Monitoring Technology Based onMulti-Sensor Cooperative Detection and Correction
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作者 Guangxin Zhang Minghui Liu +4 位作者 Shichao Cheng Minzhen Wang Changshun Zhao Hongdan Zhao Gaiming Zhong 《Energy Engineering》 EI 2024年第1期169-185,共17页
The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the buildi... The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the building to collapse.Many small changes caused the tower’s collapse,but the early staff often could not intuitively notice the changes in the tower’s state.In the current tower online monitoring system,terminal equipment often needs to replace batteries frequently due to premature exhaustion of power.According to the need for real-time measurement of power line tower,this research designed a real-time monitoring device monitoring the transmission tower attitude tilting and foundation state based on the inertial sensor,the acceleration of 3 axis inertial sensor and angular velocity raw data to pole average filtering pre-processing,and then through the complementary filtering algorithm for comprehensive calculation of tilt angle,the system meets the demand for inclined online monitoring of power line poles and towers regarding measurement accuracy,with low cost and power consumption.The optimization multi-sensor cooperative detection and correction measured tilt angle result relative accuracy can reach 1.03%,which has specific promotion and application value since the system has the advantages of unattended and efficient calculation. 展开更多
关键词 Transmission line tower tilting MULTI-SENSOR foundation state monitoring collaborative detection
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Impact of Crosswind on Steady-State and Dynamic Performance of Natural Draft Dry Cooling Tower Group:A Numerical Analysis
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作者 Xuhui Jiang Xi Zhang +4 位作者 Song Wang Ruiqiong Wang Peng Zou Jingzhou Lu Xiaoxiao Li 《Frontiers in Heat and Mass Transfer》 EI 2024年第1期193-216,共24页
This study investigates the performance of a natural draft dry cooling tower group in crosswind conditions through numerical analysis.A comprehensive three-dimensional model is developed to analyze the steady-state an... This study investigates the performance of a natural draft dry cooling tower group in crosswind conditions through numerical analysis.A comprehensive three-dimensional model is developed to analyze the steady-state and dynamic behavior of the towers.The impact of wind speed and direction on heat rejection capacity and flow patterns is examined.Results indicate that crosswinds negatively affect the overall heat transfer capacity,with higher crosswind speeds leading to decreased heat transfer.Notably,wind direction plays a significant role,particularly at 0°.Moreover,tower response time increases with higher crosswind speeds due to increased turbulence and the formation of vortices.The response times are generally similar for wind directions of 45°and 90°,but differ when facing 0,where the leeward tower exhibits a shorter response time compared to the windward tower.These findings provide valuable insights into the performance of natural draft dry cooling tower groups under crosswind conditions,which can inform the design and operation of similar systems in practical applications. 展开更多
关键词 Natural draft dry cooling tower group CROSSWIND dynamic characteristics
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Design Optimization of a Lattice Tower: Structure and Foundations
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作者 Cossi Télesphore Nounangnonhou Guy Clarence Semassou +1 位作者 Kossoun Alain Tossa Noémie Sintondji 《Open Journal of Applied Sciences》 2024年第2期483-493,共11页
Produced in power plants, electrical energy is transported to places of consumption via the electricity network. At the heart of this network are the supports that allow electricity to be efficiently transported over ... Produced in power plants, electrical energy is transported to places of consumption via the electricity network. At the heart of this network are the supports that allow electricity to be efficiently transported over long distances, guaranteeing the security and supply of energy to the various centers of use. In the construction of a line, supports occupy an important part in terms of safety and construction cost. It is therefore essential to optimize their use to reduce the cost of transmission lines. This work addresses this problem, which focuses on the optimal utilization of X-lattice towers in the construction of overhead power lines. The challenge is to reconcile the search for optimal cost and respect for the design, resistance and service constraints of the structure. To do this, a parameter having a strong correlation with the weight, foundation and construction cost of the X-lattice tower for 161 kV lines is determined as an important cost variable. This parameter is the wheelbase of the towers. The junction point between the structure and the foundations is obtained by measuring the forces at the base of the tower following the lowering of the loads. These efforts make it possible to size foundations which are of the inverted or isolated sole type. The results obtained reveal that from 8 meters in width, the wheelbase gradually changes until the optimum is obtained at 6.29 meters. With this wheelbase, the production cost is optimal. It clearly emerges from this study that the construction of lattice pylons with a wheelbase of approximately 6.29 meters makes it possible to optimize the cost of construction of 161 kV lines in the Republic of Benin. 展开更多
关键词 Lattice tower WHEELBASE COST OPTIMIZATION FOUNDATION
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Tower Semiconductor Acquisition: Advancing Intel’s Presence in the Global Market
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作者 CHEN Kangmin 《Management Studies》 2024年第1期33-41,共9页
This paper delves into the economic event surrounding Intel Corporation’s high-profile acquisition of Tower Corporation.It aims to investigate the reasons behind Intel’s decision to acquire Tower,employ the SWOT ana... This paper delves into the economic event surrounding Intel Corporation’s high-profile acquisition of Tower Corporation.It aims to investigate the reasons behind Intel’s decision to acquire Tower,employ the SWOT analysis method to evaluate the event,and examine its impact on relevant stakeholders.The findings indicate that Intel’s acquisition of Tower was driven by objectives such as strengthening business areas,expanding market share,technological innovation and development,and future development strategy.Through the application of SWOT analysis,it becomes evident that the advantages of the acquisition lie in strengthening technical capabilities and expanding business segments,while simultaneously facing challenges such as integration complexities and pressure.The significance of this paper lies in gaining a comprehensive understanding of the strategic motivations and potential impacts associated with corporate acquisitions,thereby providing valuable insights for decision-making processes.The innovation lies in the comprehensive utilization of SWOT analysis to holistically evaluate the acquisition event,enabling a thorough assessment of its various aspects.For government and policymakers,they should strength regulation of corporate takeovers to ensure fair and transparent market competition,provide support and incentives,and strength cooperation to develop common policies and norms.As for enterprises,it is advised that strategic planning and comprehensive consideration should be formulated and carried out when making acquisitions.Also,stakeholders should actively participate in and monitor the process of corporate acquisition discussion and decision-making,and strengthen cooperation to ensure fair competition,maximizing the interests of all parties. 展开更多
关键词 intel corporation tower corporation ACQUISITION strategic motivation potential impacts SWOT analysis COOPERATION
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Evaluation of Driver-Induced Human Errors in Smart Construction Tower Crane Operations Based on DEMATEL-ISM-MICMAC
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作者 Jiahao Wang Wen Si 《Journal of Applied Mathematics and Physics》 2024年第4期1541-1556,共16页
With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing facto... With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing factors, human unsafe behavior stands out as a primary cause for these incidents. This study aims to assess the human reliability of tower crane operations on smart construction sites. To proactively enhance safety measures, the research employs text mining techniques (TF-IDF-Truncated SVD-Complement NB) to identify patterns of human errors among tower crane operators. Building upon the SHEL model, the study categorizes behavioral factors affecting human reliability in the man-machine interface, leading to the establishment of the Performance Shaping Factors (PSFs) system. Furthermore, the research constructs an error impact indicator system for the intelligent construction site tower crane operator interface. Using the DEMATEL method, it analyzes the significance of various factors influencing human errors in tower crane operations. Additionally, the ISM-MICMAC method is applied to unveil the hierarchical relationships and driving-dependent connections among these influencing factors. The findings indicate that personal state, operating procedures, and physical environment directly impact human errors, while personal capability, technological environment, and one fundamental organizational management factor contribute indirectly. . 展开更多
关键词 Text Mining DEMATEL-ISM-MICMAC Performance Shaping Factors Smart Construction tower Crane Operator
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Thermal Management of Air-Cooling Lithium-Ion Battery Pack 被引量:5
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作者 Jianglong Du Haolan Tao +3 位作者 Yuxin Chen Xiaodong Yuan Cheng Lian Honglai Liu 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第11期77-82,共6页
Lithium-ion battery packs are made by many batteries, and the difficulty in heat transfer can cause many safety issues. It is important to evaluate thermal performance of a battery pack in designing process. Here, a m... Lithium-ion battery packs are made by many batteries, and the difficulty in heat transfer can cause many safety issues. It is important to evaluate thermal performance of a battery pack in designing process. Here, a multiscale method combining a pseudo-two-dimensional model of individual battery and three-dimensional computational fluid dynamics is employed to describe heat generation and transfer in a battery pack. The effect of battery arrangement on the thermal performance of battery packs is investigated. We discuss the air-cooling effect of the pack with four battery arrangements which include one square arrangement, one stagger arrangement and two trapezoid arrangements. In addition, the air-cooling strategy is studied by observing temperature distribution of the battery pack. It is found that the square arrangement is the structure with the best air-cooling effect, and the cooling effect is best when the cold air inlet is at the top of the battery pack. We hope that this work can provide theoretical guidance for thermal management of lithium-ion battery packs. 展开更多
关键词 Thermal Management of air-cooling Lithium-Ion Battery Pack
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Influence of thermal flow field of cooling tower on recirculation ratio of a direct air-cooled system for a power plant
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作者 Zhao Wanli Liu Peiqing 《Engineering Sciences》 EI 2008年第4期64-70,共7页
In order to get thermal flow field of direct air-cooled system,the hot water was supplied to the model of direct air-cooled condenser(ACC). The particle image velocimetery (PIV) experiments were carried out to get the... In order to get thermal flow field of direct air-cooled system,the hot water was supplied to the model of direct air-cooled condenser(ACC). The particle image velocimetery (PIV) experiments were carried out to get thermal flow field of a ACC under different conditions in low velocity wind tunnel,at the same time,the recirculation ratio at cooling tower was measured,so the relationship between flow field characteristics and recirculation ratio of cooling tower can be discussed. From the results we can see that the flow field configuration around cooling tower has great effects on average recirculation ratio under cooling tower. The eddy formed around cooling tower is a key reason that recirculation produces. The eddy intensity relates to velocity magnitude and direction angle,and the configuration of eddy lies on the geometry size of cooling tower. So changing the flow field configuration around cooling tower reasonably can decrease recirculation ratio under cooling tower,and heat dispel effect of ACC can also be improved. 展开更多
关键词 direct air-cooled condenser thermal flow field characteristics recirculation ratio PIV experiment
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Research and Demonstration of Direct Air-Cooling System for 600-MW Fossil-Fired Power Plants
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作者 Zhang Xiaolu 1 , Wang Jianping 2 , Hu Zhenling 3 1. China Power Investment Corporation 2. China Power Engineering Consulting Group Corporation 3. Harbin Air Conditioning Co., Ltd., 《Electricity》 2011年第4期46-51,共6页
Given the distribution feature of resources such as coal and water, the requirements for the development of Chinese power industry, and the fact of monopoly by foreign companies, it is very necessary and significant t... Given the distribution feature of resources such as coal and water, the requirements for the development of Chinese power industry, and the fact of monopoly by foreign companies, it is very necessary and significant to independently research and develop air-cooling technologies. Through experimental research, simulative calculation, process and equipment development, field tests and a demonstration project, the design and operation technologies for air-cooling system are grasped and relevant key equipment is developed. The results of the demonstration project show that the technical indicators for the air-cooling system have met or exceeded the design requirements. Part of the research results have been incorporated into the relevant national design standards. The technologies developed have been applied to more than 23 sets of thermal power units of or above 600 MW in China. 展开更多
关键词 thermal power generating unit air-cooling direct air-cooling project demonstration
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超高层工业建筑中“机械-自然-城市-人”多尺度复合设计研究——以日立电梯试验塔“H1 TOWER”为例 被引量:1
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作者 平辉 安田幸一 《南方建筑》 CSCD 北大核心 2023年第2期40-47,共8页
工业建筑因其特殊的功能和尺度,相关研究往往以结构设备技术为重心。而在技术革新、城市发展的推动下,当代工业建筑设计进入了类型多样化、技术高度化、城市景观化、使用人性化的新发展阶段。本文以日立电梯“H1 TOWER”为例,针对高速... 工业建筑因其特殊的功能和尺度,相关研究往往以结构设备技术为重心。而在技术革新、城市发展的推动下,当代工业建筑设计进入了类型多样化、技术高度化、城市景观化、使用人性化的新发展阶段。本文以日立电梯“H1 TOWER”为例,针对高速电梯试验塔这一新工业建筑类型,从机械、自然、城市、人这四种尺度对试验塔的不同要求进行梳理,对平面构成、建筑轮廓、风穴与立面、外墙细部中对意匠与技术方案的整合进行具体考察,并结合同类建筑作进一步比较分析与总结,提出多尺度复合、多专业协同将是拓展工业建筑设计维度、工程技术与城市人文融合的关键。 展开更多
关键词 电梯试验塔 高宽比 风荷载 工业建筑 城市景观
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Analysis of Air-Cooling Battery Thermal Management System for Formula Student Car
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作者 Leone Martellucci Kodekondla Kalyan Krishna 《Journal of Transportation Technologies》 2021年第3期436-454,共19页
Designing a good energy storage system represents the most important chall</span><span style="font-family:Verdana;">enge for spreading over a large scale of electric mobility. Proper thermal</... Designing a good energy storage system represents the most important chall</span><span style="font-family:Verdana;">enge for spreading over a large scale of electric mobility. Proper thermal</span> <span style="font-family:Verdana;">management is critical and guarantees optimum working temperature in a</span><span style="font-family:Verdana;"> battery pack. In the various battery thermal management technologies, air cooling is one of the most used solutions. The following work analyzes the cooling performance of the air-cooling thermal management system by choosing appropriate system parameters and analyzes using CFD simulations for accurate thermal modeling. These parameters include the influence of airflow rate </span><span style="font-family:Verdana;">and cell spacing on the configuration. The outcome of the simulations is</span><span style="font-family:Verdana;"> compared using parameters like maximum temperature, and temperature distribution in the battery module to obtain optimum results for further applications. Finally, the simulations of the optimal solution will be compared to experimental results for validation. 展开更多
关键词 BATTERY Thermal Management System air-cooling Formula Student
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Experimental Investigation of the Cooling Capacity of Gaseous Carbon Dioxide in Free Jet Expansion for Use in Portable Air-Cooling Systems
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作者 Chady Al Sayed Ludwig Vinches Stéphane Hallé 《Open Journal of Applied Sciences》 2018年第2期62-72,共11页
This paper investigates the possibility of using the free expansion of gaseous CO2 in portable air-cooling systems. The cooling capacity of the gaseous CO2 free jet expansion was calculated using three different appro... This paper investigates the possibility of using the free expansion of gaseous CO2 in portable air-cooling systems. The cooling capacity of the gaseous CO2 free jet expansion was calculated using three different approaches and the results showed that the simplified calculations would give approximated cooling values with an 11.6% maximum error. The mass flow rate, upstream pressure and cooling capacity of the gaseous CO2 decreased with time. A maximum 48.5 watts of cooling was recorded at minute 4 and a minimum value of 10.4 watts at the end of the test. The drop in cooling capacity is due to the evaporation of the liquid CO2 inside the small cylinder which cools the two-phase CO2 mixture and causes a pressure drop (from 6 MPa to 2.97 MPa), which also affects the mass flow rate of gaseous CO2 exiting the orifice (from 0.56 g/s to 0.24 g/s). If this cooling technique is to be considered in portable compact-cooling systems, the mass, pressure and cooling capacity drop with time must be solved. One of the solutions could be to cover the cylinder with a heating coat to compensate for the heat absorbed by the evaporation of the liquid CO2. 展开更多
关键词 Gaseous CO2 Free JET EXPANSION COOLING Capacity Compact air-cooling Technique
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Spray Effect on the Thermal Performances of a Dry Cooling Tower
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作者 Zhe Geng Feng Feng +5 位作者 Shuzhen Zhang Jie Li Chengwei Liu Yang Li Tiantian Liu Suoying He 《Fluid Dynamics & Materials Processing》 EI 2023年第9期2289-2304,共16页
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 cooli... 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 vary-ing 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℃ when compared with the no spray case;(2)To improve the thermal per-formance 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. 展开更多
关键词 Natural draft dry cooling tower spray strategy thermal performance SIMULATION
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Research on Representative Engineering Applications of Anemometer Towers Location in Complex TopographyWind Resource Assessment
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作者 Hao Liu Xiaoyang Zhang +3 位作者 Zhongjie Yan Yingjian Yang Qing’an Li Chang Cai 《Energy Engineering》 EI 2023年第1期163-179,共17页
The typical location and number of anemometer towers in the assessed area are the key to the accuracy of wind resource assessment in complex topography.As calculation examples,this paper used two typical complex topog... The typical location and number of anemometer towers in the assessed area are the key to the accuracy of wind resource assessment in complex topography.As calculation examples,this paper used two typical complex topography wind farms in Guangxi,Yunnan province in China.Firstly,we simulated the wind resource status of the anemometer tower in the Meteodyn WT software.Secondly,we compared the simulated wind resource with the actual measured data by the anemometer tower in the same situation.Thirdly,we analyzed the influence of anemometer tower location and quantity in the accuracy of wind resource assessment through the comparison results.The results showed that the range which the anemometer tower can represent is limited(<5 kilometers),and the prediction error more than 5%.Besides,the anemometer towers in special terrain areas(such as wind acceleration areas)cannot be used as a representative choice.The relative error of the simulated average annual wind speed by choose different number of anemometer towers is about 4%,and the grid-connected power generation more than 6%.The representative effect of anemometer towers is of crucial for improving the accuracy of wind resource assessment in engineering applications. 展开更多
关键词 Wind resource assessment anemometer tower complex topography meteodyn WT
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Safety Risk Assessment of Overturning Construction of Towering Structure Based on Cloud Matter–Element Coupled Model
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作者 Yingxue Sang Fengxia Han +2 位作者 Qing Liu Liang Qiao Shouxi Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1973-1998,共26页
Rapid urbanization has led to a surge in the number of towering structures,and overturning is widely used because it can better accommodate the construction of shaped structures such as variable sections.The complexit... Rapid urbanization has led to a surge in the number of towering structures,and overturning is widely used because it can better accommodate the construction of shaped structures such as variable sections.The complexity of the construction process makes the construction risk have certain randomness,so this paper proposes a cloudbased coupled matter-element model to address the ambiguity and randomness in the safety risk assessment of overturning construction of towering structures.In the pretended model,the digital eigenvalues of the cloud model are used to replace the eigenvalues in the matter–element basic element,and calculate the cloud correlation of the risk assessment metrics through the correlation algorithm of the cloud model to build the computational model.Meanwhile,the improved hierarchical analysis method based on the cloud model is used to determine the weight of the index.The comprehensive evaluation scores of the evaluation event are then obtained through the weighted average method,and the safety risk level is determined accordingly.Through empirical analysis,(1)the improved hierarchical analysis method based on the cloud model can incorporate the data of multiple decisionmakers into the calculation formula to determine theweights,which makes the assessment resultsmore credible;(2)the evaluation results of the cloud-basedmatter-element coupledmodelmethod are basically consistent with those of the other two commonly used methods,and the confidence factor is less than 0.05,indicating that the cloudbased physical element coupled model method is reasonable and practical for towering structure overturning;(3)the cloud-based coupled element model method,which confirms the reliability of risk level by performing Spearman correlation on comprehensive assessment scores,can provide more comprehensive information of instances compared with other methods,and more comprehensively reflects the fuzzy uncertainty relationship between assessment indexes,which makes the assessment results more realistic,scientific and reliable. 展开更多
关键词 Cloud matter-element model clouded hierarchical analysis method towering structure overturning formwork construction risk assessment
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Experimental Study on the Resistance and Splash Performances of Water Collecting Devices for Mechanical Draft Cooling Towers
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作者 Guoqing Long Guogang Zhang +3 位作者 Qi Zhang Cuilin Zhao Suoying He Fengzhong Sun 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1789-1801,共13页
In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To ex... In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To explore the feasibility of this approach for mechanical draft cooling towers,a small-scale experimental device has been built to study the resistance and splash performances of three U-type water collecting devices(WCDs)for different water flow rates and wind speeds.The experimental results show that within the considered ranges of wind speed and water flow rate,the pressure drop of the different WCDs can vary significantly.The resistance and local splash performances can also be remarkably different.Some recommendations about the most suitable system are provided.Moreover,a regression analysis of the experimental data is conducted,and the resulting fitting formulas for resistance and splash performance of WCD are reported. 展开更多
关键词 Mechanical draft cooling towers water collecting device resistance performance splash performance fitting formulas
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Influence of Wind Turbine Structural Parameters on Wind Shear and Tower Shadow Effect
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作者 Yajing Zhang Chaoyang Song Zhiguo Li 《Energy Engineering》 EI 2023年第2期501-510,共10页
To overcome the problems of natural decreases in power quality,and to eliminate wind speed fluctuation due to wind shear and tower shadow effect arising from wind turbine structural parameters,an improved prediction m... To overcome the problems of natural decreases in power quality,and to eliminate wind speed fluctuation due to wind shear and tower shadow effect arising from wind turbine structural parameters,an improved prediction model accounting for the dual effect of wind shear and tower shadow is,in this paper,built.Compared to the conventional prediction model,the proposed model contains a new constraint condition,which makes the disturbance term caused by the tower shadow effect always negative so that the prediction result is closer to the actual situation.Furthermore,wind turbine structural parameters such as hub height,rotor diameter,the diameter of the tower top,and rotor overhang on wind shear and tower shadow effect are also explored in detail.The results show that the wind shear effect became weaker with the increase in hub height.The hub height is independent of the tower shadow effect.The rotor diameter is positively correlated with the wind shear and tower shadow effect.The tower shadow effect is positively correlated with the diameter of the tower top and negatively correlated with the rotor overhang. 展开更多
关键词 Wind turbine wind shear tower shadow effect dual effect structural parameters
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A Monitoring Method for Transmission Tower Foots Displacement Based on Wind-Induced Vibration Response
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作者 Zhicheng Liu Long Zhao +2 位作者 Guanru Wen Peng Yuan Qiu Jin 《Structural Durability & Health Monitoring》 EI 2023年第6期541-555,共15页
The displacement of transmission tower feet can seriously affect the safe operation of the tower,and the accuracy of structural health monitoring methods is limited at the present stage.The application of deep learnin... The displacement of transmission tower feet can seriously affect the safe operation of the tower,and the accuracy of structural health monitoring methods is limited at the present stage.The application of deep learning method provides new ideas for structural health monitoring of towers,but the current amount of tower vibration fault data is restricted to provide adequate training data for Deep Learning(DL).In this paper,we propose a DT-DL based tower foot displacement monitoring method,which firstly simulates the wind-induced vibration response data of the tower under each fault condition by finite element method.Then the vibration signal visualization and Data Transfer(DT)are used to add tower fault data samples to solve the problem of insufficient actual data quantity.Subsequently,the dynamic response test is carried out under different tower fault states,and the tower fault monitoring is carried out by the DL method.Finally,the proposed method is compared with the traditional online monitoring method,and it is found that this method can significantly improve the rate of convergence and recognition accuracy in the recognition process.The results show that the method can effectively identify the tower foot displacement state,which can greatly reduce the accidents that occurred due to the tower foot displacement. 展开更多
关键词 tower online monitoring wind-induced response continuous wavelet transform CNN multi sensor information fusion
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