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Research on Energy-Saving Performance of Intermittent Heating for Rooms in Hot Summer&ColdWinter Zone
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作者 Guoqing Yu Nan Fang +1 位作者 Dingke Hu Wei Zhao 《Energy Engineering》 EI 2023年第7期1563-1582,共20页
In the hot summer&cold winter zone in China,intermittent heating space for rooms is widely used.However,in comparison with continuous space heating,the energy-saving performance of intermittent space heating has n... In the hot summer&cold winter zone in China,intermittent heating space for rooms is widely used.However,in comparison with continuous space heating,the energy-saving performance of intermittent space heating has not been sufficiently investigated.This paper studied the factors influencing the energy performance of intermittent heating for the representativeoffice inhot summer&coldwinter zone.Basedon theheatbalancemethod,adynamic thermalmodel of the intermittent heating roomwas built and tested by experiments.And then,it analyzed the total space heating load,the amount of energy saving and energy saving ratio of the intermittent heating under different preheating hours,occupation hours,required roomtemperatures,air change rates,overall heat transfer coefficients(U-value)of windows and wall materials.If the adjacent rooms were not heated,for a typical room occupied about 10 h a day,the energy-saving ratio of intermittent heating was about 30%compared with continuous heating.But the preheating power was higher than two times of continuous heating.The results also indicated that the occupation hours had a significant effect on energy saving amount and ratio,it should be noted that the energy saving ratio by intermittent heating was much lower than the unoccupied period ratio.Relative to other factors,the heating temperatures,room air change rates and U-value of windows,and room envelope materials had little effect on energy efficiency.If the adjacent rooms were heated in the same manner as the roomin question,the energy-saving ratio of the total load of intermittent heating was heavily reduced to 8.46%. 展开更多
关键词 Intermittent heating space heat load continuous heating hot summer&cold winter zone energy saving ratio
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Study of Flow and Heat Transfer in an Ejector-Driven Swirl Anti-Icing Chamber
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作者 Yi Tu Yuan Wu Yu Zeng 《Fluid Dynamics & Materials Processing》 EI 2024年第5期989-1014,共26页
The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic consequences.The Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annula... The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic consequences.The Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annular chamber to heat the engine inlet lip surface and prevent icing.This study employs a validated Computational Fluid Dynamics(CFD)approach to study the impact of key geometric parameters of this system on flow and heat transfer characteristics within the anti-icing chamber.Additionally,the entropy generation rate and exergy efficiency are analyzed to assess the energy utilization in the system.The research findings indicate that,within the considered flow range,reducing the nozzle specific areaφfrom 0.03061 to 0.01083 can enhance the ejection coefficient by over 60.7%.This enhancement increases the air circulating rate,thereby intensifying convective heat transfer within the SAI chamber.However,the reduction inφalso leads to a significant increase in the required bleed air pressure and a higher entropy generation rate,indicating lower exergy efficiency.The nozzle angleθnotably affects the distribution of hot and cold spots on the lip surface of the SAI chamber.Increasingθfrom 0°to 20°reduces the maximum temperature difference on the anti-icing chamber surface by 60 K. 展开更多
关键词 Swirl anti-icing heat transfer exergy efficiency hot and cold spot aircraft engine
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Experimental Study on the Performance of ORC System Based on Ultra-Low Temperature Heat Sources
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作者 Tianyu Zhou Liang Hao +2 位作者 Xin Xu Meng Si Lian Zhang 《Energy Engineering》 EI 2024年第1期145-168,共24页
This paper discussed the experimental results of the performance of an organic Rankine cycle(ORC)system with an ultra-low temperature heat source.The low boiling point working medium R134a was adopted in the system.Th... This paper discussed the experimental results of the performance of an organic Rankine cycle(ORC)system with an ultra-low temperature heat source.The low boiling point working medium R134a was adopted in the system.The simulated heat source temperature(SHST)in this work was set from 39.51°C to 48.60°C by the simulated heat source module.The influence of load percentage of simulated heat source(LPSHS)between 50%and 70%,the rotary valve opening(RVO)between 20%and 100%,the resistive load between 36Ωand 180Ωor the no-load of the generator,as well as the autumn and winter ambient temperature on the system performance were studied.The results showed that the stability of the system was promoted when the generator had a resistive load.The power generation(PG)and generator speed(GS)of the system in autumn were better than in winter,but the expander pressure ratio(EPR)was lower than in winter.Keep RVO unchanged,the SHST,the mass flow rate(MFR)of the working medium,GS,and the PG of the system increased with the increasing of LPSHS for different generator resistance load values.When the RVO was 60%,LPSHS was 70%,the SHST was 44.15°C and the resistive load was 72Ω,the highest PG reached 15.11 W.Finally,a simulation formula was obtained for LPSHS,resistance load,and PG,and its correlation coefficient was between 0.9818 and 0.9901.The formula can accurately predict the PG.The experimental results showed that the standard deviation between the experimental and simulated values was below 0.0792,and the relative error was within±5%. 展开更多
关键词 ORC load percentage of simulated heat source resistive load rotary valve opening power generation
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Genetic Analysis of Cold Tolerance at Seedling Stage and Heat Tolerance at Anthesis in Rice (Oryza sativa L.) 被引量:11
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作者 CHENG Li-rui WANG Jun-min +6 位作者 Veronica Uzokwe MENG Li-jun WANG Yun SUN Yong ZHU Linghua XU Jian-long LI Zhi-kang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第3期359-367,共9页
A set of 240 introgression lines derived from the advanced backcross population of a cross between a japonica cultivar,Xiushui 09,and an indica breeding line,IR2061,was developed to dissect QTLs affecting cold toleran... A set of 240 introgression lines derived from the advanced backcross population of a cross between a japonica cultivar,Xiushui 09,and an indica breeding line,IR2061,was developed to dissect QTLs affecting cold tolerance (CT) at seedling stage and heat tolerance (HT) at anthesis.Survival rate of seedlings (SRS) and spikelet fertility (SF),the index traits of CT and HT,showed significant differences between the two parents under stresses.A total of four QTLs (qSRS1,qSRS7,qSRS11a and qSRS11b) for CT were identified on chromosomes 1,7,11,and the Xiushui 09 alleles increased SRS at all loci except qSRS7.Four QTLs for SF were identified on chromosomes 4,5,6,and 11.These QTLs could be classified into two major types based on their behaviors under normal and stress conditions.The first was QTL expressed only under normal condition;and the second QTL was apparently stress induced and only expressed under stress.Among them,two QTLs (qSF4 and qSF6) which reduced the trait difference between heat stress and normal conditions must have contributed to HT because of their obvious contribution to trait stability,and the IR2061 allele at the qSF6 and the Xiushui 09 allele at the qSF4 improved HT,respectively.No similar QTL was found between CT at seedling stage and HT at anthesis.Therefore,it is possible to breed a new variety with CT and HT by pyramiding the favorable CT-and HT-improved alleles at above loci from Xiushui 09 and IR2061,respectively,through marker-assisted selection (MAS). 展开更多
关键词 cold tolerance heat tolerance advanced backcross population QTL mapping RICE
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Integration of Low-level Waste Heat Recovery and Liquefied Nature Gas Cold Energy Utilization 被引量:16
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作者 白菲菲 张早校 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期95-99,共5页
Two novel thermal cycles based on Brayton cycle and Rankine cycle are proposed, respectively, which integrate the recovery of low-level waste heat and Liquefied Nature Gas (LNG) cold energy utilization for power gen... Two novel thermal cycles based on Brayton cycle and Rankine cycle are proposed, respectively, which integrate the recovery of low-level waste heat and Liquefied Nature Gas (LNG) cold energy utilization for power generation. Cascade utilization of energy is realized in the two thermal cycles, where low-level waste heat,low-temperature exergy and pressure exergy of LNG are utilized efficiently through the system synthesis. The simulations are carried out using the commercial Aspen Plus 10.2, and the results are analyzed. Compared with the conventional Brayton cycle and Rankine cycle, the two novel cycles bring 60.94% and 60% in exergy efficiency, respectively and 53.08% and 52.31% in thermal efficiency, respectively. 展开更多
关键词 recovery of low-level waste heat LNG cold energy utilization power generation cascade utilization
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Microstructure, cold rolling, heat treatment, and mechanical properties of Mg-Li alloys 被引量:3
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作者 Haibin Ji Guangchun Yao Hongbin Li 《Journal of University of Science and Technology Beijing》 CSCD 2008年第4期440-443,共4页
The magnesium-lithium (Mg-Li) alloy exhibits two phase structures between 5.7wt% and 10.3wt% Li contents, consisting of the a (hcp) Mg-rich and the β (bcc) Li-rich phases, at room temperature. In the experimen... The magnesium-lithium (Mg-Li) alloy exhibits two phase structures between 5.7wt% and 10.3wt% Li contents, consisting of the a (hcp) Mg-rich and the β (bcc) Li-rich phases, at room temperature. In the experiment, Mg-5Li-2Zn, Mg-9Li-2Zn, Mg-16Li-2Zn, Mg-22Li-2Zn, Mg-5Li-2Zn-2Ca, Mg-9Li-2Zn-2Ca, Mg-16Li-2Zn-2Ca, and Mg-22Li-2Zn-2Ca (wt%) were melted. During the melting process, the flux, which was composed of lithium chloride (LiCl) and lithium fluoride (LiF) in the proportion of 3:1 (mass ratio) and argon gas were used to protect the alloys from oxidation. The microstructure, mechanical properties, and cold-rolling workability of the wrought alloys were studied. The crystal grain of the alloys (adding Ga) is fine . The hardness of the studied alloys decreases with an increase in element Li. The density of the studied alloys is in the range of 1.187 to 1.617 g/cm^3. The reduction of the Mg-16Li-2Zn and Mg-22Li-2Zn alloys can exceed 85% at room temperature. The Mg-9Li-2Zn-2Ca alloy was heat treated at 300℃ for 8, 12, 16, and 24 h, respectively. The optimum heat treatment of the Mg-9Li-2Zn-2Ca alloy is 300℃×12h by metallographic observation and by studying the mechanical properties of the alloys. 展开更多
关键词 Mg-Li alloy Mg-Li-Zn alloy cold rolling heat treatment MICROSTRUCTURE mechanical properties
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Numerical Analysis of Doublet Wells for Cold Energy Storage on Heat Damage Treatment in Deep Mines 被引量:11
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作者 HE Man-chao ZHANG Yi +1 位作者 GUO Dong-ming QIAN Zeng-zhen 《Journal of China University of Mining and Technology》 EI 2006年第3期278-282,共5页
Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Ma... Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Machine Systems (HEMSs), to store cold energy is a key to solve the heat damage problems in deep mines. Based on the geological conditions, thermodynamic and hydraulic parameters of Jiahe Mine, the isotherms in the period of cold energy storage and refrigeration and the volumes of cold water within different temperature ranges of the cold energy storage well were numerically analyzed. The results show that 1) with the same pumped and injected water volumes, the lower the temperature of injected water is, the larger the volume.of cold water in the cold energy storage well is. With the larger volume, the effect of cold energy storage is better. 2) the larger the volumes of pumped and reinjected water frigeration is better. And 3) without disturbance, the volume and temperature of cold water in the cold energy storage well can keep unchanged or have only a little change for a long time. Therefore the technology of doublet wells for cold energy storage is feasible and the cold energy storage aquifers can meet the requirement of the technology. 展开更多
关键词 deep mine heat damage treatment numerical simulation AQUIFER cold energy storage
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Investigation on automated loading of dynamic 3D heat source during welding simulation 被引量:3
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作者 胡广旭 董志波 +2 位作者 魏艳红 宋奎晶 占小红 《China Welding》 EI CAS 2011年第2期41-45,共5页
Since loading complexand dynamic heat source is a difficult job during welding simulation process, methods are studied to add the load automatically. Firstly, an expert module for selecting welding heat source model i... Since loading complexand dynamic heat source is a difficult job during welding simulation process, methods are studied to add the load automatically. Firstly, an expert module for selecting welding heat source model is founded based on simulation knowledge and experienc Secondly, a method named as "High order routine" is presented, which creates subroutines of 3D dynamic heat source m'od, el for user. Then an automated tool is presented to load the welding heat source boundary based on Marc software. The tool uses Marc command file to robustly achieve the process. At last, an electron beam welding heat model is presented to express the "toading method. 展开更多
关键词 heat source. automated loading electron beam welding high order routine
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Effects of sustained cold and heat stress on energy intake, growth and mitochondrial function of broiler chickens 被引量:8
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作者 ZHANG Shao-shuai SU Hong-guang +3 位作者 ZHOU Ying LI Xiu-mei FENG Jing-hai ZHANG Min-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第10期2336-2342,共7页
To study the correlation of broiler chickens with energy intake, growth and mitochondrial function which exposed to sustained cold and heat stress and to find out the comfortable temperature, 288 broiler chickens(21-... To study the correlation of broiler chickens with energy intake, growth and mitochondrial function which exposed to sustained cold and heat stress and to find out the comfortable temperature, 288 broiler chickens(21-day with(748±26) g, 144 males and 144 females) were divided randomly into six temperature-controlled chambers. Each chamber contained six cages including eight AA broilers per cage, each cage as a repeat. After acclimation for one week(temperature, 21℃; relative humidity, 60%), the temperature of each chamber was adjusted(finished within 1 h) respectively to 10, 14, 18, 22, 26, or 30℃(RH, 60%) for a 14-day experimental period. After treatment, gross energy intake(GEI), metabolizable energy intake(MEI), the ratio of MEI/BW, metabolizability, average daily gain(ADG), the concentration of liver mitochondria protein and cytochrome c oxidase(CCO) were measured respectively. Our results confirmed that when the temperature over 26℃ for 14 days, GEI, MEI and CCO activities were decreased significantly(P〈0.05), but the concentration of liver mitochondria protein was increased and metabolizability of broilers was not influenced(P〉0.05). Compared with treatment for 14 days, the ratio of MEI/body weight(BW) were also decreased when the temperature over 26℃ after temperature stress for 7 days(P〈0.05), meanwhile mitochondrial protein concentration was increased at 10℃ and CCO activity was not affected(P〉0.05). Additionally at 22℃, the ADG reached the maximal value. When kept in uncomfortable temperatures for a long time, the ADG and CCO activities of broiler were reduced, which was accompanied by mitochondrial hyperplasia. In summary, our study focused on the performance of broilers during sustained cold and heat environmental temperatures ranging from 10 to 30℃. From the point of view of energy utilization, moreover, 22 to 26℃ is comfortable for 28–42 day s broilers. And these could provide the theoretical basis on the high efficient production. 展开更多
关键词 broiler chicken cytochrome c oxidase energy intake metabolizability sustained cold and heat stress
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Fast Algorithm for Prediction of Airfoil Anti-icing Heat Load 被引量:2
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作者 Xueqin Bu Rui Yang +2 位作者 Jia Yu Xiaobin Shen Guiping Lin 《Energy and Power Engineering》 2013年第4期493-497,共5页
Many flight and icing conditions should be considered in order to design an efficient ice protection system to prevent ice accretion on the aircraft surface. The anti-icing heat load is the basic knowledge for the des... Many flight and icing conditions should be considered in order to design an efficient ice protection system to prevent ice accretion on the aircraft surface. The anti-icing heat load is the basic knowledge for the design of a thermal anti-icing system. In order to help the design of the thermal anti-icing system and save the design time, a fast and efficiency method for prediction the anti-icing heat load is investigated. The computation fluid dynamics (CFD) solver and the Messinger model are applied to obtain the snapshots. Examples for the calculation of the anti-icing heat load using the proper orthogonal decomposition (POD) method are presented and compared with the CFD simulation results. It is shown that the heat loads predicted by POD method are in agreement with the CFD computation results. Moreover, it is obviously to see that the POD method is time-saving and can meet the requirement of real-time prediction. 展开更多
关键词 ANTI-ICING heat load PROPER ORTHOGONAL DECOMPOSITION
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Evolution of microstructure, phase composition, and tensile properties of severely cold deformed titanium metastable β alloy in rapid continuous heating 被引量:3
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作者 P.E.MARKOVSKY V.I.BONDARCHUK +1 位作者 YU.V.MATVIYCHUK O.P.KARASEVSKA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1365-1371,共7页
Influence of severe cold deformation of titanium alloy Ti-1.5%A1-6.8%Mo-4.5%Fe in metastable β condition on the evolution of phase composition, microstructure, and tensile properties during continuous rapid heating w... Influence of severe cold deformation of titanium alloy Ti-1.5%A1-6.8%Mo-4.5%Fe in metastable β condition on the evolution of phase composition, microstructure, and tensile properties during continuous rapid heating was studied. As-deformed alloy was characterized by quasi-amorphous single-phase β condition with an abnormal temperature dependence of electric resistance that was normalized after 48 h exposure at room temperature as a result of isothermal ω phase precipitation. Subsequent rapid heating with a rate of 5 ℃/s caused recovery and recrystallization. Tensile properties of the alloy after different treatments were determined and discussed. 展开更多
关键词 titanium alloy severe cold deformation rapid heating recovery and recrystallization phase composition MICROSTRUCTURE mechanical properties
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Effect of heat treatment on microstructure and properties of single crystal copper cold-welded joints 被引量:1
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作者 Huang Yong Ran Xiaolong +1 位作者 Yan Xiaojuan Guo Tingbiao 《China Welding》 EI CAS 2019年第2期1-9,共9页
With the means of electron backscattered diffraction(EBSD),mechanical properties test and digital eddy current metal conductivity,the single crystal copper cold-welded joint was tested and analyzed,the structure chang... With the means of electron backscattered diffraction(EBSD),mechanical properties test and digital eddy current metal conductivity,the single crystal copper cold-welded joint was tested and analyzed,the structure change of cold-welded joint and the effect of heat treating on the structure and property of cold-welded joint were discussed.The results show that:The deformation area of the single crystal copper cold welded joint is broken,the crystalline grain at the interface of the joint is refined,and the single crystal structure is still maintained in the base metal area.The hardness of the deformation area increases greatly,the conductivity of the joint does not change much,and the tensile strength of the joint reaches about 70%of that of the base metal.At the interface of the heat treating joint,the single crystal structure of the deformation area and the base metal area are destroyed,and the grains grow up at the interface and the orientation is different.The hardness of the joint interface is much lower than that of the non-heat treating joint,the electrical conductivity of the joint is good,and the tensile strength of the joint is higher than that of the base metal. 展开更多
关键词 single CRYSTAL copper cold pressure welding heat treatment CONDUCTIVITY
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Role of heat balance on the microstructure evolution of cold spray coated AZ31B with AA7075 被引量:3
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作者 Bahareh Marzbanrad Mohammad Hadi Razmpoosh +1 位作者 Ehsan Toyserkani Hamid Jahed 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第4期1467-1478,共12页
A promising solid-state coating mechanism based on the cold spray technique provides highly advantageous conditions on thermal-sensitive magnesium alloys.To study the effect of heat balance in cold spray coating on mi... A promising solid-state coating mechanism based on the cold spray technique provides highly advantageous conditions on thermal-sensitive magnesium alloys.To study the effect of heat balance in cold spray coating on microstructure,experiments were designed to successfully coat AA7075 on AZ31B with two different heat balance conditions to yield a coated sample with tensile residual stress and a sample with compressive residual stress in both coating and substrate.The effects of coating temperature on the microstructure of magnesium alloy and the interfaces of coated samples were then analyzed by SEM,EBSD,TEM in high-and low-heat input coating conditions.The interface of the AA7075 coating and magnesium alloy substrate under both conditions consists of a narrow-band layer with very fine grains,followed by columnar grains of magnesium that have grown perpendicular to the interface.At higher temperatures,this layer became wider.No intermetallic phase was detected at the interface under either condition.It is shown that the microstructure of the substrate was affected by coating temperature,leading to stress relief,dynamic recrystallization and even dynamic grain growth of magnesium under high temperature.Reducing the heat input and increasing the heat transfer decreased microstructural changes in the substrate. 展开更多
关键词 cold spraying heat balance Microstructural analysis Coating interface Magnesium Alloy AZ31B Residual Stress
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Integrated Behavior of Carbon and Copper Alloy Heat Sink Under Different Heat Loads and Cooling Conditions 被引量:1
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作者 李化 李建刚 +1 位作者 陈俊浚 胡建生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第4期2923-2925,共3页
An actively water-cooled limiter has been designed for the long pulse operation of an HT-7 device, by adopting an integrated structure-doped graphite and a copper alloy heat sink with a super carbon sheet serving as a... An actively water-cooled limiter has been designed for the long pulse operation of an HT-7 device, by adopting an integrated structure-doped graphite and a copper alloy heat sink with a super carbon sheet serving as a compliant layer between them. The behaviors of the integrated structure were evaluated in an electron beam facility under different heat loads and cooling conditions. The surface temperature and bulk temperature distribution were carefully measured by optical pyrometers and thermocouples under a steady state heat flux of 1 to 5 MW/m^2 and a water flow rate of 3 m^3/h, 4.5 m^3/h and 6 m^3/h, respectively. It was found that the surface temperature increased rapidly with the heat flux rising, but decreased only slightly with the water flow rate rising. The surface temperature reached approximately 1200℃ at 5 MW/m^2 of heat flux and 6 m^3/h of water flow. The primary experimental results indicate that the integrated design meets the requirements for the heat expelling capacity of the HT-7 device. A set of numerical simulations was also completed, whose outcome was in good accord with the experimental results. 展开更多
关键词 HT-7 tokamak carbon and copper alloy heat sink heat loads cooling conditions numerical simulation
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Experimental and Simulation Studies on Cold Welding Sealing Process of Heat Pipes 被引量:4
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作者 Yong LI Shengle CHEN +2 位作者 Jinlong HUANG Yuying YAN Zhixin ZENG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期332-343,共12页
Sealing quality strongly affects heat pipe performance, but few studies focus on the process of heat pipe sealing. Cold welding sealing technology based on a stamping process is applied for heat pipe sealing. The bond... Sealing quality strongly affects heat pipe performance, but few studies focus on the process of heat pipe sealing. Cold welding sealing technology based on a stamping process is applied for heat pipe sealing. The bonding mechanism of the cold welding sealing process (CWSP) is investigated and compared with the experimental results obtained from the bonding interface analysis. An orthogonal experiment is conducted to observe the effects of various parameters, including the sealing gap, sealing length, sealing diameter, and sealing velocity on bonding strength. A method with the utilization of saturated vapor pressure inside a copper tube is proposed to evaluate bonding strength. A corresponding finite element model is developed to investigate the effects of sealing gap and sealing velocity on plastic deformation during the cold welding process. Effects of various parameters on the bonding strength are determined and it is found that the sealing gap is the most critical factor and that the sealing velocity contributes the least effect. The best parameter combination (AIB3CID3, with a 0.5 mm sealing gap, 6 mm sealing length, 3.8 mm sealing diameter, and 50 mm/s sealing velocity) is derived within the experimental parameters. Plastic deformation results derived from the finite element model are consistent with those from the experiment. The instruction for the CWSP of heat pipes and the design of sealing dies of heat pipes are provided. 展开更多
关键词 cold welding sealing process(CWSP) · Bonding strength · heat pipe · Orthogonal experimen
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Investigation on automated loading of dynamic 3D heat source model for welding simulation 被引量:2
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作者 Hu Guangxu Yang Xingya +1 位作者 Yu Xingbin Wei Yanhong 《China Welding》 CAS 2022年第3期48-52,共5页
Since programing complex and dynamic heat source model for welding simulation is a complex job,the parametric methods are studied in this paper.Firstly,an overall flow to achieve automatically modeling welding was int... Since programing complex and dynamic heat source model for welding simulation is a complex job,the parametric methods are studied in this paper.Firstly,an overall flow to achieve automatically modeling welding was introduced.Secondly,an expert module rule for selecting welding heat source model was founded,which is based on simulation knowledge and experiences.Thirdly,a modularity routine method was investigated using writing with C++programing,which automatically creates subroutines of 3D dynamic heat source model for user.To realize the dynamic weld path,the local weld path coordinate system was moved in the global coordinate system and it is used to model the direction of weld gun,welding path and welding pose.The weld path data file was prepared by the automatic tool for the welding heat source subroutines.All above functions were integrated in the user interface and the connection with architecture was introduced.At last,a laser beam welding heat source modeling was automatically modeled and the weld pool geometry was compared with the reported literature.It demonstrated that the automated tool is valid for welding simulation.Since modeling became convenient for welding simulation using the tool proposed,it could be easy and useful for welding engineers to acquire the needed information. 展开更多
关键词 welding heat source welding simulation 3D dynamic heat source model automated loading of heat source
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CoNi nanoparticles anchored inside carbon nanotube networks by transient heating:Low loading and high activity for oxygen reduction and evolution 被引量:1
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作者 Chengfeng Zhu Wei Yang +5 位作者 Jiangtao Di Sha Zeng Jian Qiao Xiaona Wang Bo Lv Qingwen Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期63-71,共9页
Transitional metal alloy and compounds have been developed as the low cost and efficient bifunctional electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).However,a high mass loading o... Transitional metal alloy and compounds have been developed as the low cost and efficient bifunctional electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).However,a high mass loading of these catalysts is commonly needed to achieve acceptable catalytic performance,which could cause such problems as battery weight gain,mass transport blocking,and catalyst loss.We report herein the preparation of fine CoNi nanoparticles(5-6 nm)anchored inside a nitrogendoped defective carbon nanotube network(CoNi@N-DCNT)by a transient Joule heating method.When utilized as an electrocatalyst for oxygen reduction and evolution in alkaline media,the CoNi@N-DCNT film catalyst with a very low mass loading of 0.06 mg cm^(-2) showed excellent bifunctional catalytic performance.For ORR,the onset potential(Eonset)and the half-wave potential(E_(1/2))were 0.92 V versus reversible hydrogen electrode(vs.RHE)and 0.83 V(vs.RHE),respectively.For OER,the potential at the current density(J)of 10 mA cm^(-2)(E_(10))was 1.53 V,resulting in an overpotential of 300 mV much lower than that of the commercial RuO_(2) catalyst(320 mV).The potential gap between E_(1/2) and E_(10) was as small as 0.7 V.Considering the low mass loading,the mass activity at E_(10) reached at 123.2 A g^(-1),much larger than that of the RuO_(2) catalyst and literature results of transitional metal-based bifunctional catalysts.Moreover,the CoNi@N-DCNT film catalyst showed very good long-term stability during the ORR and OER test.The excellent bifunctional catalytic performance could be attributed to the synergistic effect of the bimetal alloy. 展开更多
关键词 Transient Joule heating method Carbon nanotubes Nano alloy Low loading Bifunctional catalyst
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Effect of particle loading on heat transfer enhancement in a gas-solid suspension cross flow 被引量:1
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作者 周劲松 骆仲泱 +2 位作者 高翔 倪明江 岑可法 《Journal of Zhejiang University Science》 CSCD 2002年第4期381-386,共6页
Heat transfer between gas-solid multiphase flow and tubes occurs in many industry processes, such as circulating fluidized bed process, pneumatic conveying process, chemical process, drying process, etc. This paper fo... Heat transfer between gas-solid multiphase flow and tubes occurs in many industry processes, such as circulating fluidized bed process, pneumatic conveying process, chemical process, drying process, etc. This paper focuses on the influence of the presence of particles on the heat transfer between a tube and gas-solid suspension. The presence of particles causes positive enhancement of heat transfer in the case of high solid loading ratio, but heat transfer reduction has been found for in the case of very low solid loading ratio (M s of less than 0.05 kg/kg). A useful correlation incorporating solid loading ratio, particle size and flow Reynolds number was derived from experimental data. In addition, the k-ε two-equation model and the Fluctuation-Spectrum- Random-Trajectory Model (FSRT Model) are used to simulate the flow field and heat transfer of the gas-phase and the solid-phase, respectively. Through coupling of the two phases the model can predict the local and total heat transfer characteristics of tube in gas-solid cross flow. For the total heat transfer enhancement due to particles loading the model predictions agreed well with experimental data. 展开更多
关键词 Multiphase flow heat transfer Particle loading
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Therapeutic Actions of the Chinese Herbal Formulae with Cold and Heat Properties and Their Effects on Ultrastructures of Synoviocytes in Rats of the Collagen-Induced Arthritis 被引量:5
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作者 李梢 吕爱平 +1 位作者 贾宏伟 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2002年第4期296-302,共7页
The therapeutic actions of Qing Luo Yin (QLY清络饮) with heat property and Wen Luo Yin (WLY温络饮) with cold property on pain, swelling of the ankle, arthritis index and ultrastructures of synoviocytes were compared i... The therapeutic actions of Qing Luo Yin (QLY清络饮) with heat property and Wen Luo Yin (WLY温络饮) with cold property on pain, swelling of the ankle, arthritis index and ultrastructures of synoviocytes were compared in rats of type II collagen-induced arthritis (CIA), with tripterygium glycosidorum (TG) used as control. The results indicated that both QLY and WLY could reduce pain, swelling of the ankle and the arthritis index of CIA, and QLY had better effects in reducing the swelling of the ankle and controlling the secondary pathological lesions as compared with WLY. Investigation on the ultrastructures of synoviocytes indicated that both QLY and WLY could reduce the number of Golgi apparatus, rough surface endoplasmic reticulum, dense bodies, matrix filaments and vacuoles so as to suppress the excessive secretion of synoviocytes in rats of CIA. 展开更多
关键词 Therapeutic Actions of the Chinese Herbal Formulae with cold and heat Properties and Their Effects on Ultrastructures of Synoviocytes in Rats of the Collagen-Induced Arthritis RER
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Cold welding sealing of copper-water micro heat pipe ends 被引量:3
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作者 汤勇 陆龙生 +1 位作者 邓大祥 袁冬 《中国有色金属学会会刊:英文版》 CSCD 2009年第3期568-574,共7页
The quality of micro heat pipe(MHP) is strongly affected by sealing technology. Based on the analysis of requirements of sealing technology, a cold welding technology was presented to seal MHP. In the cold welding pro... The quality of micro heat pipe(MHP) is strongly affected by sealing technology. Based on the analysis of requirements of sealing technology, a cold welding technology was presented to seal MHP. In the cold welding process, compression force was used to flatten micro groove copper(MGC) tube. Then the bonding of MGC tube was reached because of intensively plastic deformation of MGC tube under pressure. It is found that the plastic deformation area of the cold welding of MGC tube can be divided into three sections. The deformation of micro grooves in each section was investigated; the influence of the dimensions of cylindrical heads on the weld joint shape and strength was studied; and a comparison between smooth copper tube and MGC tube was done. The results show that a groove compression stage exists in the cold welding of MGC tube besides a flattened stage and a melting stage. 展开更多
关键词 密封技术 微型热管 铜管 冷焊 塑性变形 MGC 焊接技术 焊接工艺
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