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Low-energy-consumption temperature swing system for CO_(2) capture by combining passive radiative cooling and solar heating 被引量:2
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作者 Ying-Xi Dang Peng Tan +3 位作者 Bin Hu Chen Gu Xiao-Qin Liu Lin-Bing Sun 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期507-515,共9页
Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative coo... Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption. 展开更多
关键词 CO_(2)capture Solar heating Passive radiative cooling Temperature swing adsorption
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A coupled thermo-mechanical peridynamic model for fracture behavior of granite subjected to heating and water-cooling processes 被引量:1
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作者 Luming Zhou Zhende Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2006-2018,共13页
Thermal damage and thermal fracture of rocks are two important indicators in geothermal mining projects.This paper investigates the effects of heating and water-cooling on granite specimens at various temperatures.The... Thermal damage and thermal fracture of rocks are two important indicators in geothermal mining projects.This paper investigates the effects of heating and water-cooling on granite specimens at various temperatures.The laboratory uniaxial compression experiments were also conducted.Then,a coupled thermo-mechanical ordinary state-based peridynamic(OSB-PD)model and corresponding numerical scheme were developed to simulate the damage of rocks after the heating and cooling processes,and the change of crack evolution process was predicted.The results demonstrate that elevated heating temperatures exacerbate the thermal damage to the specimens,resulting in a decrease in peak strength and an increase in ductility of granite.The escalating occurrence of thermal-induced cracks significantly affects the crack evolution process during the loading phase.The numerical results accurately reproduce the damage and fracture characteristics of the granite under different final heating temperatures(FHTs),which are consistent with the test results in terms of strength,crack evolution process,and failure mode. 展开更多
关键词 Peridynamics(PD) GRANITE heating and cooling Damage and fracture Uniaxial compression
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Personal Thermal Management by Radiative Cooling and Heating 被引量:1
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作者 Shidong Xue Guanghan Huang +3 位作者 Qing Chen Xungai Wang Jintu Fan Dahua Shou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期225-267,共43页
Maintaining thermal comfort within the human body is crucial for optimal health and overall well-being.By merely broadening the setpoint of indoor temperatures,we could significantly slash energy usage in building hea... Maintaining thermal comfort within the human body is crucial for optimal health and overall well-being.By merely broadening the setpoint of indoor temperatures,we could significantly slash energy usage in building heating,ventilation,and air-conditioning systems.In recent years,there has been a surge in advancements in personal thermal management(PTM),aiming to regulate heat and moisture transfer within our immediate surroundings,clothing,and skin.The advent of PTM is driven by the rapid development in nano/micro-materials and energy science and engineering.An emerging research area in PTM is personal radiative thermal management(PRTM),which demonstrates immense potential with its high radiative heat transfer efficiency and ease of regulation.However,it is less taken into account in traditional textiles,and there currently lies a gap in our knowledge and understanding of PRTM.In this review,we aim to present a thorough analysis of advanced textile materials and technologies for PRTM.Specifically,we will introduce and discuss the underlying radiation heat transfer mechanisms,fabrication methods of textiles,and various indoor/outdoor applications in light of their different regulation functionalities,including radiative cooling,radiative heating,and dual-mode thermoregulation.Furthermore,we will shine a light on the current hurdles,propose potential strategies,and delve into future technology trends for PRTM with an emphasis on functionalities and applications. 展开更多
关键词 Personal thermal management Radiative cooling and heating Thermal comfort Dynamic thermoregulation
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Thin paints for durable and scalable radiative cooling 被引量:1
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作者 Shanquan Liu Fei Zhang +3 位作者 Xingyu Chen Hongjie Yan Wei Chen Meijie Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期176-182,I0006,共8页
Passive daytime radiative cooling(PDRC) is environment-friendly without energy input by enhancing the coating's solar reflectance(R_(solar)) and thermal emittance(ε_(LWIR)) in the atmosphere's long-wave infra... Passive daytime radiative cooling(PDRC) is environment-friendly without energy input by enhancing the coating's solar reflectance(R_(solar)) and thermal emittance(ε_(LWIR)) in the atmosphere's long-wave infrared transmission window.However,high R_(solar) is usually achieved by increasing the coating's thickness,which not only increases materials' cost but also impairs heat transfer.Additionally,the desired high R_(solar) is vulnerable to dust pollution in the outdoors.In this work,a thin paint was designed by mixing hBN plates,PFOTS,and IPA. R_(solar)=0.963 and ε_(LWIR)=0.927 was achieved at a thickness of 150 μm due to the high backscattering ability of scatters.A high through-plane thermal conductivity(~1.82 W m^(-1) K^(-1)) also can be obtained.In addition,the porous structure coupled with the binder PFOTS resulted in a contact angle of 154°,demonstrating excellent durability under dust contamination.Outdoor experiments showed that the thin paint can obtain a 2.3℃ lower temperature for sub-ambient cooling than the reference PDRC coating in the daytime.Furtherly,the above-ambient heat dissipation performance can be enhanced by spraying the thin paint on a 3D heat sink,which was 15.7℃ lower than the reference 1D structure,demonstrating excellent performance for durable and scalable PDRC applications. 展开更多
关键词 Radiative cooling heat dissipation Solar reflectance Thermal emittance Contact angle
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Application and prospect of the fluid cooling system of solar arrays for probing the Sun 被引量:1
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作者 Kangli Bao Xiaofei Zhu +5 位作者 Jianchao Feng Liu Liu Xiaofeng Zhang Zhiming Cai Jun Lin Yonghe Zhang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期62-70,共9页
The Solar Close Observations and Proximity Experiments(SCOPE)mission,which has been proposed by the Yunnan Observatories,Chinese Academy of Sciences,aiming to operate at a distance of 5 to 10 solar radii from the Sun,... The Solar Close Observations and Proximity Experiments(SCOPE)mission,which has been proposed by the Yunnan Observatories,Chinese Academy of Sciences,aiming to operate at a distance of 5 to 10 solar radii from the Sun,plans to complete the in situ detection of the solar eruption process and observation of the magnetic field structure response.The solar flux received by the satellite ranges from 10^(3) to 10^(6) Wm^(-2),which poses challenges for thermal management of the solar arrays.In this work,the solar array cooling system of the Parker Solar Probe is discussed,the developments of the fluid loop technique are reviewed,and a research plan for a next-generation solar array cooling system is proposed.This paper provides a valuable reference for novel thermal control systems in spacecraft for solar observation. 展开更多
关键词 In situ detection of solar eruption Solar array cooling system Pumped fluid loop High heat flux dissipation
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Effects of cooling rate on solution heat treatment of as-cast A356 alloy 被引量:13
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作者 杨长林 李远兵 +2 位作者 党波 吕贺宾 刘峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3189-3196,共8页
The effect of cooling rate of the solidification process on the following solution heat treatment of A356 alloy was investigated,where the cooling rates of 96 K/s and 3 K/s were obtained by the step-like metal mold.Th... The effect of cooling rate of the solidification process on the following solution heat treatment of A356 alloy was investigated,where the cooling rates of 96 K/s and 3 K/s were obtained by the step-like metal mold.Then the eutectic silicon morphology evolution and tensile properties of the alloy samples were observed and analyzed after solution heat treatment at 540 °C for different time.The results show that the high cooling rate of the solidification process can not only reduce the solid solution heat treatment time to rapidly modify the eutectic silicon morphology,but also improve the alloy tensile properties.Specially,it is found that the disintegration,the spheroidization and coarsening of eutectic silicon of A356 alloy are completed during solution heat treatment through two stages,i.e.,at first,the disintegration and spheroidization of the eutectic silicon mainly takes place,then the eutectic silicon will coarsen. 展开更多
关键词 A356 aluminum alloy solution heat treatment eutectic silicon cooling rate
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Aqueous ammonia solution cooling absorption refrigeration driven by fishing boat diesel exhaust heat 被引量:5
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作者 陈亚平 林陈敏 田莹 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期333-338,共6页
A solution cooling absorption(SCA)approach is proposed to modify the aqueous ammonia absorption refrigerat-ion cycle using the strong solution from the absorber to cool the forepart of the absorption in the cycle fo... A solution cooling absorption(SCA)approach is proposed to modify the aqueous ammonia absorption refrigerat-ion cycle using the strong solution from the absorber to cool the forepart of the absorption in the cycle for reclaiming some portion of absorption heat.As a consequence of raised temperature at the inlet,the strong solution partially boils at the outlet of the solution heat exchanger,and diminishes the thermal heat consumption of the heat source.The calculation results show that the coefficient of performance(COP)of this modified cycle is about 28.3% higher than that of the traditional cycle under typical conditions;while the required heat transfer area of the total heat exchangers of the cycle is somewhat less than that of the traditional one.The capacity of refrigeration with the new absorption cycle is more than doubled in contrast to the adsorption scheme with an identical configuration.It is sufficient to supply a fishing boat the chilling capacity for preservation of fishing products with the modified cycle chiller driven by its diesel engine exhaust. 展开更多
关键词 aqueous ammonia absorption refrigeration solution cooling absorption waste heat recovery heat and mass transfer coefficient of performance
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HEAT TRANSFER CHARACTERISTICS OF NEW COOLING TECHNIQUE BASED ON THERMAL DRIVING 被引量:2
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作者 毛军逵 杨敏 +1 位作者 常海萍 卜继兴 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期125-131,共7页
A new cooling technique based on thermal driving in high centrifugal field (TDHCF) is developed for gas turbine rotational components, such as turbine blades. The key point of TDHCF is to enhance heat transfer by th... A new cooling technique based on thermal driving in high centrifugal field (TDHCF) is developed for gas turbine rotational components, such as turbine blades. The key point of TDHCF is to enhance heat transfer by the fluid thermal driving in closed loop small channels placed in the high centrifugal field. Heat transfer characteristics of the new cooling technique are analyzed. In experiments, two different fluids (liquid water and Freon R12) are used as thermal driving media (fluid inside the loop channel). And the channel width d is 1 mm and the height h is 30 mm. The temperature is measured by thermocouples and an average heat transfer coefficient KH is defined to indicate heat transfer capacity of TDHCF. Experimental results show that KH is enhanced when heat flux and the rotating speed increase. And thermal properties of thermal driving media are also influenced by KH. Larger KH can be achieved by using Freon R12 as thermal driving medium compared with using liquid water. It can increase to 2 300 W/(m^2 · K) and it is much higher than that of the normal air cooling method (usually at the level of 600-1200 W/(m^2·K)). All fundamental studies of TDHCF show that there actually exists thermal driving in the closed loop small channel in the centrifugal field to improve heat transfer characteristics. 展开更多
关键词 heat transfer thermal driving centrifugal field cooling technology
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Thermal comfort assessment and energy consumption analysis of ground-source heat pump system combined with radiant heating/cooling 被引量:1
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作者 路诗奎 张小松 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期52-57,共6页
A new ground source heat pump system combined with radiant heating/cooling is proposed, and the principles and the advantages of the system are analyzed. A demonstration of the system is applied to a rebuilt building... A new ground source heat pump system combined with radiant heating/cooling is proposed, and the principles and the advantages of the system are analyzed. A demonstration of the system is applied to a rebuilt building: Xijindu exhibition hall, which is located in Zhenjiang city in China. Numerical studies on the thermal comfort and energy consumption of the system are carded out by using TRNSYS software. The results indicate that the system with the radiant floor method or the radiant ceiling method shows good thermal comfort without mechanical ventilation in winter. However, the system with either of the methods should add mechanical ventilation to ensure good comfort in summer. At the same level of thermal comfort, it can also be found that the annual energy consumption of the radiant ceiling system is less than that of the radiant floor system. 展开更多
关键词 ground-source heat pump radiant heating/cooling thermal comfort energy consumption
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Construction and realization of the knowledge base and inference engine of an IDSS model for air-conditioning cooling/heating sources selection
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作者 刘颖 王如竹 +1 位作者 李云飞 张小松 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期136-141,共6页
The knowledge representation mode and inference control strategy were analyzed according to the specialties of air-conditioning cooling/heating sources selection. The constructing idea and working procedure for knowle... The knowledge representation mode and inference control strategy were analyzed according to the specialties of air-conditioning cooling/heating sources selection. The constructing idea and working procedure for knowledge base and inference engine were proposed while the realization technique of the C language was discussed. An intelligent decision support system (IDSS) model based on such knowledge representation and inference mechanism was developed by domain engineers. The model was verified to have a small kernel and powerful capability in list processing and data driving, which was successfully used in the design of a cooling/heating sources system for a large-sized office building. 展开更多
关键词 AIR-CONDITIONING cooling/heating sources intelligent decision support system knowledge base inference engine
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Decoupled thermal–hydraulic analysis of an air-cooled separated heat pipe for spent fuel pools under natural convection 被引量:1
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作者 Hui-Lin Xue Jian-Jie Cheng +3 位作者 Wei-Hao Ji Wen-Jin Li Han-Zhong Tao Wei Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期183-197,共15页
An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal ... An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS. 展开更多
关键词 Decoupled analysis Separated heat pipe CAP1400 Finned tube radiator Passive cooling
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Variations in Surface Urban Heat Island and Urban Cool Island Intensity:A Review Across Major Climate Zones 被引量:1
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作者 Muhammad Sadiq KHAN Sami ULLAH CHEN Liding 《Chinese Geographical Science》 SCIE CSCD 2023年第6期983-1000,共18页
The climate has an impact on the urban thermal environment,and the magnitude of the surface urban heat island(SUHI)and urban cool island(UCI)vary across the world’s climatic zones.This literature review investigated:... The climate has an impact on the urban thermal environment,and the magnitude of the surface urban heat island(SUHI)and urban cool island(UCI)vary across the world’s climatic zones.This literature review investigated:1)the variations in the SUHI and UCI intensity under different climatic backgrounds,and 2)the effect of vegetation types,landscape composition,urban configuration,and water bodies on the SUHI.The SUHI had a higher intensity in tropical(Af(tropical rainy climate,Köppen climate classification),Am(tropical monsoon climate),subtropical(Cfa,subtropical humid climate),and humid continental(Dwa,semi-humid and semi-arid monsoon climate)climate zones.The magnitude of the UCI was low compared to the SUHI across the climate zones.The cool and dry Mediterranean(Cfb,temperate marine climate;Csb,temperate mediterranean climate;Cfa)and tropical climate(Af)areas had a higher cooling intensity.For cities with a desert climate(BWh,tropical desert climate),a reverse pattern was found.The difference in the SUHI in the night-time was greater than in the daytime for most cities across the climate zones.The extent of green space cooling was related to city size,the adjacent impervious surface,and the local climate.Additionally,the composition of urban landscape elements was more significant than their configuration for sustaining the urban thermal environment.Finally,we identified future research gaps for possible solutions in the context of sustainable urbanization in different climate zones. 展开更多
关键词 urban heat island intensity(SUHI) urban cool island intensity(UCI) day-night surface urban heat island(SUHI) climate zones landscape composition and configuration sustainable urbanization
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A Financial Approach to Evaluate an Optimized Combined Cooling, Heat and Power System 被引量:20
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作者 Shahab Bahrami Farahbakhsh Safe 《Energy and Power Engineering》 2013年第5期352-362,共11页
Iran’s removing subsidy from energy carrier in four years ago leads to spike electricity price dramatically. This abrupt change increases the interest on distributed generation (DG) because of its several benefits su... Iran’s removing subsidy from energy carrier in four years ago leads to spike electricity price dramatically. This abrupt change increases the interest on distributed generation (DG) because of its several benefits such as lower electricity generation price. In Iran among all type of DGs, because of wide natural gas network infrastructure and several incentives that government legislated to support combined cooling, heat and power (CCHP) investors, this type of technology is more prevalent in comparison with other technologies. Between existing CCHP technologies, certain economic choices are to be taken into account. For different buildings with different load curves, suitable size and operation of CCHP should be calculated to make the project more feasible. If CCHP does not well suited for a position, then the whole energy efficiency would be plunged significantly. In this paper, a model to find the optimal size and operation of CCHP and auxiliary boiler for any users is proposed by considering an integrated view of electricity and natural gas network using GAMS software. Then this method is applying for a hospital in Tehran as a real case study. Finally, by applying COMFAR III software, useful financial parameters and sensitivity analysis are calculated. 展开更多
关键词 Combined cooling heat and Power (CCHP) Energy HUB Optimal SIZE FINANCIAL Analysis
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Initiative Optimization Operation Strategy and Multi-objective Energy Management Method for Combined Cooling Heating and Power 被引量:4
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作者 Feng Zhao Chenghui Zhang Bo Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第4期385-393,共9页
This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power U+0028 CCHP U+0029 with storage systems. Initially, the initiative ... This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power U+0028 CCHP U+0029 with storage systems. Initially, the initiative optimization operation strategy of CCHP system in the cooling season, the heating season and the transition season was formulated. The energy management of CCHP system was optimized by the multi-objective optimization model with maximum daily energy efficiency, minimum daily carbon emissions and minimum daily operation cost based on the proposed initiative optimization operation strategy. Furthermore, the pareto optimal solution set was solved by using the niche particle swarm multi-objective optimization algorithm. Ultimately, the most satisfactory energy management scheme was obtained by using the technique for order preference by similarity to ideal solution U+0028 TOPSIS U+0029 method. A case study of CCHP system used in a hospital in the north of China validated the effectiveness of this method. The results showed that the satisfactory energy management scheme of CCHP system was obtained based on this initiative optimization operation strategy and multi-objective energy management method. The CCHP system has achieved better energy efficiency, environmental protection and economic benefits. © 2014 Chinese Association of Automation. 展开更多
关键词 CARBON cooling cooling systems Energy efficiency Energy management heatING Multiobjective optimization OPTIMIZATION Pareto principle
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Numerical Simulation of Three-dimensional Heat and Mass Transfer in Spray Cooling of Converter Gas in a Venturi Scrubber 被引量:3
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作者 LU Tao WANG Kuisheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期745-754,共10页
In order to predict the pressure drop, collection efficiency, velocity, temperature and mole fraction of vapor in an industrial venturi scrubber with water spraying for converter gas cooling, a three-dimensional model... In order to predict the pressure drop, collection efficiency, velocity, temperature and mole fraction of vapor in an industrial venturi scrubber with water spraying for converter gas cooling, a three-dimensional model of heat and mass transfer with phase change is established. The gas flow and liquid droplets are treated as a continuous phase with a Eulerian approach and as a discrete phase with a Lagrangian approach, respectively. The coupled problem of heat, force, and mass transfers between gas flow and liquid droplets is solved by a commercial computational fluid dynamics(CFD) package, FLUENT. The numerical results show that the water injections have an important influence on the distributions of pressure, velocity, temperature, and mole fraction of vapor, especially for the spraying region in the throat. In the spraying region, the pressure drop is higher and the velocity is lower than in other regions due to the gas-droplet drag, while the temperature is lower because the droplet absorbs large amounts of heat from the high temperature gas and the mole fraction of vapor is higher due to the phase change of the liquid droplet. A number of cases with different Water-to-gas volume flow ratios and baffle openings were simulated. The dependence of pressure drop, velocity, temperature, mole fraction of vapor, and collection efficiency on both the water-to-gas volume flow ratio and baffle opening are analyzed. The good agreements between simulation results and experiment data of pressure drop, temperature, and collection efficiency validate the model. The model should facilitate optimization of the venturi scrubber design in order to give better performance with lower pressure drops and higher collection efficiency. 展开更多
关键词 numerical simulation heat and mass transfer spray cooling converter gas venturi scrubber
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Experimental Investigation of Solar Panel Cooling by a Novel Micro Heat Pipe Array 被引量:4
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作者 Xiao Tang Zhenhua Quan Yaohua Zhao 《Energy and Power Engineering》 2010年第3期171-174,共4页
A novel micro heat pipe array was used in solar panel cooling. Both of air-cooling and water-cooling conditions under nature convection condition were investigated in this paper. Compared with the ordinary solar panel... A novel micro heat pipe array was used in solar panel cooling. Both of air-cooling and water-cooling conditions under nature convection condition were investigated in this paper. Compared with the ordinary solar panel, the maximum difference of the photoelectric conversion efficiency is 2.6%, the temperature reduces maximally by 4.7℃, the output power increases maximally by 8.4% for the solar panel with heat pipe using air-cooling, when the daily radiation value is 26.3 MJ. Compared with the solar panel with heat pipe using air-cooling, the maximum difference of the photoelectric conversion efficiency is 3%, the temperature reduces maximally by 8℃, the output power increases maximally by 13.9% for the solar panel with heat pipe using water-cooling, when the daily radiation value is 21.9 MJ. 展开更多
关键词 Solar PANEL cooling PHOTOELECTRIC CONVERSION Efficiency Micro heat PIPE ARRAY
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Transient Heat Transfer Study of Direct Contact Condensation of Steam in Spray Cooling Water 被引量:2
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作者 Yiping Wang Yunfa Hu +1 位作者 Qunwu Huang Yong Cui 《Transactions of Tianjin University》 EI CAS 2018年第2期131-143,共13页
We conducted a transient experimental investigation of steam–water direct contact condensation in the absence of noncondensible gas in a laboratory-scale column with the inner diameter of 325 mm and the height of 104... We conducted a transient experimental investigation of steam–water direct contact condensation in the absence of noncondensible gas in a laboratory-scale column with the inner diameter of 325 mm and the height of 1045 mm. We applied a new analysis method for the steam state equation to analyze the molar quantity change in steam over the course of the experiment and determined the transient steam variation. We also investigated the influence of flow rates and temperatures ofcooling water on the efficiency ofsteam condensation. Our experimental results show that appropriate increasing of the cooling water flow rate can significantly accelerate the steam condensation. We achieved a rapid increase in the total volumetric heat transfer coefficient by increasing the flow rate of cooling water, which indicated a higher thermal convection between the steam and the cooling water with higher flow rates. We found that the temperature ofcooling water did not play an important role on steam condensation. This method was confirmed to be effective for rapid recovering ofsteam. 展开更多
关键词 Direct contact CONDENSATION STEAM SPRAY cooling water Transient heat TRANSFER performance STEAM state equation VOLUMETRIC heat TRANSFER coeffi cient
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Changes of heating and cooling degree days over China in response toglobal warming of 1.5℃, 2℃, 3℃ and 4℃ 被引量:8
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作者 SHI Ying ZHANG Dong-Feng +1 位作者 XU Ying ZHOU Bo-Tao 《Advances in Climate Change Research》 SCIE CSCD 2018年第3期192-200,共9页
Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over Ea... Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over East Asia using the regional climate model version 4.4 (RegCM4.4)driven by the global models of CSIRO-Mk3-6-0, EC-EARTH, HadGEM2-ES, and MPI-ESM-MR. Under global warming of 1.5℃, 2℃, 3℃,and 4℃, significant decrease of HDD can be found over China without considering population factor, with greater decrease over high elevationand high latitude regions, including the Tibetan Plateau, the northern part of Northeast China, and Northwest China; while population-weightedHDD increased in areas where population will increase in the future, such as Beijing, Tianjin, parts of southern Hebei, northern Shandong andHenan provinces. Similarly, the CDD projections with and without considering population factor are largely different. Specifically, withoutconsidering population, increase of CDD were observed over most parts of China except the Tibetan Plateau where the CDD remained zerobecause of the cold climate even under global warming; while considering population factor, the future CDD decreases in South China andincreases in North China, the Sichuan Basin, and the southeastern coastal areas, which is directly related to the population changes. The differentfuture changes of HDD and CDD when considering and disregarding the effects of population show that population distribution plays animportant role in energy consumption, which should be considered in future research. 展开更多
关键词 REGIONAL CLIMATE model Global WARMING of 1.5 2℃ 3℃ and 4℃ heating DEGREE DAYS cooling DEGREE DAYS China
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Numerical simulation of heat transfer and flow of cooling air in triangular wavy fin channels 被引量:3
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作者 倪明龙 陈亚平 +1 位作者 董聪 吴嘉峰 《Journal of Central South University》 SCIE EI CAS 2014年第7期2759-2765,共7页
Numerical computation models of air cooling heat transfer and flow behaviors in triangular wavy fin channels(TWFC) were established with structural parameters of fins considered.The air side properties of heat transfe... Numerical computation models of air cooling heat transfer and flow behaviors in triangular wavy fin channels(TWFC) were established with structural parameters of fins considered.The air side properties of heat transfer coefficient and pressure drop are displayed with variable structural parameters of fins and inlet velocities of cooling air.Within the range of simulation,TWFC has the best comprehensive performance when inlet velocity vin=4-10 m/s.Compared with those of straight fins,the simulation results reveal that the triangular wavy fin channels are of higher heat transfer performances especially with the fin structural parameters of fin-height Fh=9.0 mm,fin-pitch Fp=2.5-3.0 mm,fin-wavelength λ=14.0-17.5 mm and fin-wave-amplitude A=1.0-1.2 mm.The correlations of both heat transfer factor and friction factor are presented,and the deviations from the experimental measurements are within 20%. 展开更多
关键词 triangular wavy fins heat transfer coefficients pressure drops plate-fin heat exchangers air cooling
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Pathological changes in the lung and brain of mice during heat stress and cooling treatment 被引量:10
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作者 Zhi-feng Liu Bing-ling Li +4 位作者 Hua-sheng Tong You-qing Tang Qiu-lin Xu Jin-qiang Guo Lei Su 《World Journal of Emergency Medicine》 CAS 2011年第1期50-53,共4页
BACKGROUND: Heatstroke often leads to multiple organ dysfunction syndrome (MODS) with a death rate of 40% or a neurological morbidity of 30%. These high rates in patients with heatstroke are largely due to the prog... BACKGROUND: Heatstroke often leads to multiple organ dysfunction syndrome (MODS) with a death rate of 40% or a neurological morbidity of 30%. These high rates in patients with heatstroke are largely due to the progression of heat stress to MODS, resulting in no specifi c treatment available. This study aimed to develop a mouse model of heat stress and determine the pathological changes in the lung and brain during heat stress and cooling treatment.METHODS: A mouse model of heat stress was established in a pre-warmed incubator set at 35.5 ± 0.5°C and with a relative humidity of 60% ± 5%. Rectal temperature was monitored, and at a temperature of 39 °C, 40 °C, 41 °C, or 42 °C, the mice were sacrifi ced. The remaining animals were removed from the incubator and cooled at an ambient temperature of 25 ± 0.5 °C and a humidity of 35% ± 5% for 12 or 24 hours at a temperature of 41 °C or for 6 hours at a temperature of 42 °C. The control mice were sham-heated at a temperature of 25 ± 0.5 °C and a humidity of 35% ± 5%. The lungs and brains of all animals were isolated. Hematoxylin and eosin staining and light microscopy were performed to detect pathological changes.RESULTS: All mice demonstrated a uniform response to heat stress. A low degree of heat stress induced marked pathological changes of the lungs. With the rise of the temperature to 42°C, progressively greater damage to the lungs with further congestion of the lung matrix, asystematic hemorrhage of alveolar space, abscission of alveolar epithelial cells, and disappearance of pulmonary alveolus tissue structure were detected. However, absorption of congestion and hemorrhage as well as recovery of pulmonary alveolus tissue structure was observed following cooling treatment at an ambient temperature. With a low degree of heat stress, the brain only showed moderate edema. Neuronal denaturation and necrosis were detected at a temperature of 42°C. Interestingly, the lesions in the brain were further aggravated at 42 °C regardless of cooling treatment, but recovery was observed after cooling treatment at 41 °C.CONCLUSIONS: The pathological changes of the lungs and brain of mice showed distinctive lesions following heat stress and cooling treatment, and they were correlated with the time and duration of cooling treatment. The results of this study are helpful for further study of the mechanisms linking heatstroke. 展开更多
关键词 heat stress heatSTROKE cooling treatment LUNG BRAIN Pathological change MODS
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