Field measurements on thermal comfort were carried out in a building with double-skin faade from January 14th to 16th,2009.Data are obtained by measurements of physical parameters and a questionnaire survey is conduct...Field measurements on thermal comfort were carried out in a building with double-skin faade from January 14th to 16th,2009.Data are obtained by measurements of physical parameters and a questionnaire survey is conducted at the same time in 27 offices of the building.The subjective survey involves questions on demographic information of the occupants,health status,environmental comfort conditions and acceptance.A total of 150 occupants are investigated and 131 questionnaires are completed.The statistical data presents the distributions of predicted mean vote,mean thermal sensation vote,mean thermal comfort vote,thermal acceptability,etc.The results show that low relative humidity is the main reason causing thermal discomfort.The greatest discomfort is dry mouth and eye dryness which are caused by low relative humidity.The females are verified to be more sensitive than the males.Meanwhile,a double-skin faade represents a good noise insulation effect while the glare problem is still unresolved.展开更多
An accurate finite element （ FE） model was constructed to examine the hysteretic behavior of double-skin steel-concrete composite box （ DSCB） piers for further understanding the seismic performance of DSCB piers;...An accurate finite element （ FE） model was constructed to examine the hysteretic behavior of double-skin steel-concrete composite box （ DSCB） piers for further understanding the seismic performance of DSCB piers; where the local buckling behavior of steel tubes, the confinement of the in-filled concrete and the interface action between steel tube and in-filled concrete were considered. The accuracy of the proposed FE model was verified by the bidirectional cyclic loading test results. Based on the validated FE model, the effects of some key parameters, such as section width to steel thickness ratio, slenderness ratio, aspect ratio and axial load ratio on the hysteretic behavior of DSCB piers were investigated. Finally, the skeleton curve model of DSCB piers was proposed. The numerical simulation results reveal that the peak strength and elastic stiffness decrease with the increase of the section width to steel thickness ratio. Moreover, the increase of the slenderness ratio may result in a significant reduction in the peak strength and elastic stiffness while the ultimate displacement increases. The proposed skeleton curve model can be taken as a reference for seismic performance analyses of the DSCB piers.展开更多
The mathematic model of heat transfer through ventilated double glazing was verified with the measured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and w...The mathematic model of heat transfer through ventilated double glazing was verified with the measured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement facility.After the model validation,the double-skin facade assessment was carried out through simulation with ESP-r software integrating thermal simulation and air low net work module.The air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn week.The differences of chimney effect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventilated double skin facade were presented.展开更多
Dynamic simulation of a double-skin façade(DSF)with computational fluid dynamics(CFD)can be challenging due to the lack of validated models and benchmarking datasets.Furthermore,there is a lack of consensus in th...Dynamic simulation of a double-skin façade(DSF)with computational fluid dynamics(CFD)can be challenging due to the lack of validated models and benchmarking datasets.Furthermore,there is a lack of consensus in the scientific community on what constitutes a successfully validated DSF model.The present review study identifies simulation trends and research gaps for DSFs simulated with CFD.Additionally,this article presents a series of CFD simulations in which key aspects of the DSF modelling are varied:2D or 3D modelling approaches,turbulence viscosity models(TVMs),radiation models,and wall function.These simulation results are compared to the empirical data(both temperature and velocity fields)of a benchmark test with laboratory-controlled boundary conditions.This analysis shows that using the k-εRNG model with enhanced wall treatment and surface-to-surface(S2S)radiation model yields the best results for the 2D case of natural convection flow.Moreover,it is shown that accounting for the velocity field in the validation process is essential to ensure the suitability of a model.Finally,the authors advocate for the use of selected dimensionless numbers to improve the comparability of the different DSF scientific studies.This would also help to identify relevant experimental datasets for validation and suitable CFD simulation settings for specific DSF cases.展开更多
The CFD simulation accuracy mostly depends on the appropriate setting of boundary conditions and numerical simulation parameters.This study shows the influence of two types of boundary condition settings on the CFD si...The CFD simulation accuracy mostly depends on the appropriate setting of boundary conditions and numerical simulation parameters.This study shows the influence of two types of boundary condition settings on the CFD simulation results of Double-Skin Facade(DSF)for a specific problem.These two boundary settings are the constant temperature on the DSF surfaces called Boundary A,and Boundary B is defined via solar radiation using the Discrete Ordinate radiation Model(DOM).The paper verified both the numerical simulations using the experimental data.Comparing the numerical results of two types of boundaries with experimental data shows that both cases underestimated the values lower than 5.2 K and 0.1 m/s for the temperature and velocity respectively at the regarded measured points.Boundary A gives more accurate temperature prediction results,while Boundary B shows velocity magnitude closer to the measurements in the middle height of the cavity;the average temperature and velocity differences between the two boundary types are 0.6 K and 0.003 m/s respectively which are negligible.Finally,the selection of boundary conditions depends on study purposes,however,when the DSF is equipped with blinds and if there is not enough data in hand but the exact value of solar irradiation,using the Boundary B approach is suggested;it can provide reasonable results associated with multi-type of thermal boundary conditions at the same time.Furthermore,if the goal is to investigate the flow pattern in the DSF,Boundary B is argued to perform better than the constant temperature boundary condition.展开更多
Apartments account for over 60%of total residential buildings and consume a significant portion of primary energy in South Korea.Various energy efficiency measures have been implemented for both new apartment construc...Apartments account for over 60%of total residential buildings and consume a significant portion of primary energy in South Korea.Various energy efficiency measures have been implemented for both new apartment constructions and existing apartment retrofits.Old apartment structures have poor thermal performances,resulting in a high energy consumption.The South Korean government initiated retrofitting projects to improve the energy efficiency in old apartments.Apartment owners typically replace old windows with high-performance windows;however,there is still a demand for better and more innovative retrofit methods for a highly improved energy efficiency.This paper proposes an advanced double-skin façade(DSF)system to replace existing balcony windows in old apartments.Considering the cold climate conditions of Seoul,South Korea,it mainly discusses heating energy savings.Three case models were developed:Base-Case with existing apartment,Case-1 with typical retrofitting,and Case-2 with the proposed DSF system.The EnergyPlus simulation program was used to develop simulation models for a floor radiant heating system.A typical gas boiler was selected for low-temperature radiant system modeling.The air flow network method was used to model the proposed DSF system.Five heating months,i.e.,November to March,and one representative day,i.e.,January 24,were selected for detailed analysis.The main heat loss areas consist of windows,walls,and infiltration.The results reveal that the apartment with the DSF retrofit saves 38.8%on the annual heating energy compared to the Base-Case and 35.2%compared to Case-1.展开更多
To study the seismic performance of double-skin steelconcrete composite box（ DSCB） piers, a total of 11 DSCB pier specimens were tested under bidirectional cyclic loading. The effects of the loading pattern, the ste...To study the seismic performance of double-skin steelconcrete composite box（ DSCB） piers, a total of 11 DSCB pier specimens were tested under bidirectional cyclic loading. The effects of the loading pattern, the steel plate thickness, the axial load ratio, the slenderness ratio and the aspect ratio were taken into consideration. The damage evolution process and failure modes of the tested specimens are presented in detail. Test results are also discussed in terms of the hysteretic curve, skeleton curve, ductility and energy dissipation capacity of DSCB pier specimens. It can be concluded that the hysteretic performance of DSCB piers in one direction is affected and weakened by the cyclic loading in the other direction. DSCB piers under bidirectional cyclic loading exhibit good performance in terms of load carrying capacity, ductility, and energy dissipation capacity. Overall, DSCB piers can meet the basic aseismic requirements. The research results can be taken as a reference for using DSCB piers as high piers in bridges in strong earthquakeprone areas.展开更多
Double-skin facades(DSF)are a technique developed for colder climates,so few people think about whether or not it can also be used for hot-summer and cold-winter zones in China.After analyzing the problems of using DS...Double-skin facades(DSF)are a technique developed for colder climates,so few people think about whether or not it can also be used for hot-summer and cold-winter zones in China.After analyzing the problems of using DSF for hot-summer zones,this paper explored on the possibility of applying DSF in hot-summer and cold-winter zones in China.The main existing research methods for DSF were also collected and commented.If properly managed,the ventilated DSF with controlled shading devices can be used even in hot summer in China.展开更多
Aluminum alloys have been widely applied in coastal and marine structures because of their superior sustainability and corrosion resistance.Concrete-filled double-skin aluminum tubular columns(CFDAT)possess higher str...Aluminum alloys have been widely applied in coastal and marine structures because of their superior sustainability and corrosion resistance.Concrete-filled double-skin aluminum tubular columns(CFDAT)possess higher strength and better ductility than traditional reinforced concrete structures.However,few studies have been conducted on numerical simulation methods for circular CFDATs.Specifically,there has been no experimental or numerical study on intermediate-to-slender circular CFDATs.Here,a comprehensive numerical study was conducted on a modeling method for the first time to simulate the axial behavior of a slender circular CFDAT.This study outlines the development of numerical modeling techniques and presents a series of comparative studies using various material nonlinearities,confinement effects,and nonlinearity of the initial geometric imperfections for a slender column.The numerical results were compared with more than 80 previously available stub and slender experimental test results for verification.It was confirmed that the proposed numerical technique was reliable and accurate for simulating the axial behavior of intermediate and slender circular CFDAT.Furthermore,a parametric study was conducted to investigate the effects of geometric and material properties on the axial capacity of the CFDAT.Additionally,the slenderness and strength-to-width ratio of CFDAT were compared with those of concrete-filled double-skin steel tubular columns(CFDST).The simulated axial strengths were compared with those predicted using AS 5100 and AISC 360.New design equations for the CFDATs should be proposed based on AS 5100.展开更多
The key role of the building envelope in achieving building energy efficiency and indoor comfort for the user has been long established.The most promising-and innovative-strategy for the building envelope of the futur...The key role of the building envelope in achieving building energy efficiency and indoor comfort for the user has been long established.The most promising-and innovative-strategy for the building envelope of the future is based on a dynamic,active and integrated solution,that is able to optimize the thermal performance,integrate the active elements and systems,and exploit energy from renewable sources.This paper illustrates the most relevant results of a decade-long research activity carried out on active and integrated building envelopes at the Politecnico di Torino,in which numerical analyses and experimental campaigns,involving test cells and field monitoring,have been performed.The overall performances of different façade modules and the thermo-physical behaviour of various components,under different operating strategies,are presented and discussed.The analysis provides information on the contribution of each subsystem,e.g.glazing,sun-shading devices,natural and mechanical ventilation,...to the achieved energy efficiency and the overall performances of different typologies of Double-Skin Façades(DSFs)and Advanced Integrated Façades(AIFs).展开更多
Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer(FRP)-concrete-steel double-skin tubular members(DSTMs).The strip method was used to calculate the section momentcurvature ...Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer(FRP)-concrete-steel double-skin tubular members(DSTMs).The strip method was used to calculate the section momentcurvature curves of the 3 specimens and 12 models.A theoretical formula is presented for the flexural strength of DSTMs.The test results show that the tension zone of the specimen FRP tubes was in hoop compression while the compression zone was in hoop tension.The load-carrying capacity did not decrease even when the mid-span deflection reached about 1/24 of the span length.The tests,simulation and theoretical analysis resulted in a simplified formula for the flexural strength of DSTMs and a tri-linear moment-curvature model was expressed as a function of the section bending stiffness for DSTMs.展开更多
Various techniques for creating a comfortable thermal environment and saving energy have been proposed and employed in residential buildings in many countries, including Japan. For these techniques to be introduced, e...Various techniques for creating a comfortable thermal environment and saving energy have been proposed and employed in residential buildings in many countries, including Japan. For these techniques to be introduced, existing houses should be renovated. Among the techniques available, installation of additional inner windows is effective in creating a comfortable and energy-efficient living environment. In the present research, the effect of additional inner windows on the thermal environment and energy saving was investigated by measuring indoor climates. Windows were renovated in two rooms on the fourth floor of a four-story reinforced concrete building. Air temperatures, the humidity, the global solar radiation on horizontal and vertical surfaces, radiant temperatures, and the electricity consumption of air-conditioners were measured. A comparison of these vatues before and after the installation of inner- windows showed that the thermal environment and energy saving had improved. Results obtained from a thermal model agreed well with measured results by changing the value of solar transmittance and heat transmission coefficient of the glazing forlowing renovation. Furthermore, in a questionnaire survey conducted in summer, more than half of the occupants answered ＂cornfortabte＂ to a question on the overall thermal comfort.展开更多
Performance of Photovoltaic-double skin façade(Photovoltaic-DSF)system in summer has been critical.Owing to high solar ingress,cooling requirement of a building significantly increases.Photovoltaic-DSF system pro...Performance of Photovoltaic-double skin façade(Photovoltaic-DSF)system in summer has been critical.Owing to high solar ingress,cooling requirement of a building significantly increases.Photovoltaic-DSF system provides a shield and controls the heat gain through fenestration in the interior spaces.In the present article,mathematical correlations are developed for energy characterization of forced-ventilated Photovoltaic-DSF system in India’s hot summer zone i.e.Jaipur.The Photovoltaic-DSF system has been installed and monitored for Jaipur’s summer months(May to July).L25 Orthogonal array of design parameters(air cavity thickness,air velocity,and PV panel’s transparency)and their respective levels have been developed using Taguchi design to perform experiments.Based on experimental results,multiple linear regression has been used to forecast solar heat gain coefficient,PVs electrical power and daylighting illuminance indoors as function of design factors.The statistical significance of mathematical relationships is sorted by variance analysis,which is found to be in good accord with field measurements(R2>0.90).The proposed correlations are pragmatic in designing Photovoltaic-DSF systems for hot summer conditions.The Photovoltaic-DSF system with 30%transmittance and air velocity of 5 metres per second in 200 mm air cavity thickness achieved maximum energy performance in hot summers.展开更多
基金The National Key Technology R&D Program of Chinaduring the 11th Five-Year Plan Period(No.2008BAJ12B05)
文摘Field measurements on thermal comfort were carried out in a building with double-skin faade from January 14th to 16th,2009.Data are obtained by measurements of physical parameters and a questionnaire survey is conducted at the same time in 27 offices of the building.The subjective survey involves questions on demographic information of the occupants,health status,environmental comfort conditions and acceptance.A total of 150 occupants are investigated and 131 questionnaires are completed.The statistical data presents the distributions of predicted mean vote,mean thermal sensation vote,mean thermal comfort vote,thermal acceptability,etc.The results show that low relative humidity is the main reason causing thermal discomfort.The greatest discomfort is dry mouth and eye dryness which are caused by low relative humidity.The females are verified to be more sensitive than the males.Meanwhile,a double-skin faade represents a good noise insulation effect while the glare problem is still unresolved.
基金The National Natural Science Foundation of China(No.51678141,51378112)the Open Fund from the National Engineering Laboratory for Technology of Geological Disaster Prevention in Land Transportation,Southwest Jiaotong University(No.SWJTUGGS-2014001)
文摘An accurate finite element （ FE） model was constructed to examine the hysteretic behavior of double-skin steel-concrete composite box （ DSCB） piers for further understanding the seismic performance of DSCB piers; where the local buckling behavior of steel tubes, the confinement of the in-filled concrete and the interface action between steel tube and in-filled concrete were considered. The accuracy of the proposed FE model was verified by the bidirectional cyclic loading test results. Based on the validated FE model, the effects of some key parameters, such as section width to steel thickness ratio, slenderness ratio, aspect ratio and axial load ratio on the hysteretic behavior of DSCB piers were investigated. Finally, the skeleton curve model of DSCB piers was proposed. The numerical simulation results reveal that the peak strength and elastic stiffness decrease with the increase of the section width to steel thickness ratio. Moreover, the increase of the slenderness ratio may result in a significant reduction in the peak strength and elastic stiffness while the ultimate displacement increases. The proposed skeleton curve model can be taken as a reference for seismic performance analyses of the DSCB piers.
基金Supported by Shanghai Science and Technology Supporting Program(08DZ1203500)City University of Hong Kong(7002004)+1 种基金Shanghai Local University Fund(071605124)Undergraduates Education Fund for University of Shanghai
文摘The mathematic model of heat transfer through ventilated double glazing was verified with the measured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement facility.After the model validation,the double-skin facade assessment was carried out through simulation with ESP-r software integrating thermal simulation and air low net work module.The air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn week.The differences of chimney effect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventilated double skin facade were presented.
文摘Dynamic simulation of a double-skin façade(DSF)with computational fluid dynamics(CFD)can be challenging due to the lack of validated models and benchmarking datasets.Furthermore,there is a lack of consensus in the scientific community on what constitutes a successfully validated DSF model.The present review study identifies simulation trends and research gaps for DSFs simulated with CFD.Additionally,this article presents a series of CFD simulations in which key aspects of the DSF modelling are varied:2D or 3D modelling approaches,turbulence viscosity models(TVMs),radiation models,and wall function.These simulation results are compared to the empirical data(both temperature and velocity fields)of a benchmark test with laboratory-controlled boundary conditions.This analysis shows that using the k-εRNG model with enhanced wall treatment and surface-to-surface(S2S)radiation model yields the best results for the 2D case of natural convection flow.Moreover,it is shown that accounting for the velocity field in the validation process is essential to ensure the suitability of a model.Finally,the authors advocate for the use of selected dimensionless numbers to improve the comparability of the different DSF scientific studies.This would also help to identify relevant experimental datasets for validation and suitable CFD simulation settings for specific DSF cases.
文摘The CFD simulation accuracy mostly depends on the appropriate setting of boundary conditions and numerical simulation parameters.This study shows the influence of two types of boundary condition settings on the CFD simulation results of Double-Skin Facade(DSF)for a specific problem.These two boundary settings are the constant temperature on the DSF surfaces called Boundary A,and Boundary B is defined via solar radiation using the Discrete Ordinate radiation Model(DOM).The paper verified both the numerical simulations using the experimental data.Comparing the numerical results of two types of boundaries with experimental data shows that both cases underestimated the values lower than 5.2 K and 0.1 m/s for the temperature and velocity respectively at the regarded measured points.Boundary A gives more accurate temperature prediction results,while Boundary B shows velocity magnitude closer to the measurements in the middle height of the cavity;the average temperature and velocity differences between the two boundary types are 0.6 K and 0.003 m/s respectively which are negligible.Finally,the selection of boundary conditions depends on study purposes,however,when the DSF is equipped with blinds and if there is not enough data in hand but the exact value of solar irradiation,using the Boundary B approach is suggested;it can provide reasonable results associated with multi-type of thermal boundary conditions at the same time.Furthermore,if the goal is to investigate the flow pattern in the DSF,Boundary B is argued to perform better than the constant temperature boundary condition.
基金supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)the Ministry of Trade,Industry&Energy(MOTIE)of the Republic of Korea(No.20172010000370).
文摘Apartments account for over 60%of total residential buildings and consume a significant portion of primary energy in South Korea.Various energy efficiency measures have been implemented for both new apartment constructions and existing apartment retrofits.Old apartment structures have poor thermal performances,resulting in a high energy consumption.The South Korean government initiated retrofitting projects to improve the energy efficiency in old apartments.Apartment owners typically replace old windows with high-performance windows;however,there is still a demand for better and more innovative retrofit methods for a highly improved energy efficiency.This paper proposes an advanced double-skin façade(DSF)system to replace existing balcony windows in old apartments.Considering the cold climate conditions of Seoul,South Korea,it mainly discusses heating energy savings.Three case models were developed:Base-Case with existing apartment,Case-1 with typical retrofitting,and Case-2 with the proposed DSF system.The EnergyPlus simulation program was used to develop simulation models for a floor radiant heating system.A typical gas boiler was selected for low-temperature radiant system modeling.The air flow network method was used to model the proposed DSF system.Five heating months,i.e.,November to March,and one representative day,i.e.,January 24,were selected for detailed analysis.The main heat loss areas consist of windows,walls,and infiltration.The results reveal that the apartment with the DSF retrofit saves 38.8%on the annual heating energy compared to the Base-Case and 35.2%compared to Case-1.
基金The National Natural Science Foundation of China(No.5117810151378112)the Doctoral Fund of Ministry of Education(No.20110092110011)
文摘To study the seismic performance of double-skin steelconcrete composite box（ DSCB） piers, a total of 11 DSCB pier specimens were tested under bidirectional cyclic loading. The effects of the loading pattern, the steel plate thickness, the axial load ratio, the slenderness ratio and the aspect ratio were taken into consideration. The damage evolution process and failure modes of the tested specimens are presented in detail. Test results are also discussed in terms of the hysteretic curve, skeleton curve, ductility and energy dissipation capacity of DSCB pier specimens. It can be concluded that the hysteretic performance of DSCB piers in one direction is affected and weakened by the cyclic loading in the other direction. DSCB piers under bidirectional cyclic loading exhibit good performance in terms of load carrying capacity, ductility, and energy dissipation capacity. Overall, DSCB piers can meet the basic aseismic requirements. The research results can be taken as a reference for using DSCB piers as high piers in bridges in strong earthquakeprone areas.
文摘Double-skin facades(DSF)are a technique developed for colder climates,so few people think about whether or not it can also be used for hot-summer and cold-winter zones in China.After analyzing the problems of using DSF for hot-summer zones,this paper explored on the possibility of applying DSF in hot-summer and cold-winter zones in China.The main existing research methods for DSF were also collected and commented.If properly managed,the ventilated DSF with controlled shading devices can be used even in hot summer in China.
文摘Aluminum alloys have been widely applied in coastal and marine structures because of their superior sustainability and corrosion resistance.Concrete-filled double-skin aluminum tubular columns(CFDAT)possess higher strength and better ductility than traditional reinforced concrete structures.However,few studies have been conducted on numerical simulation methods for circular CFDATs.Specifically,there has been no experimental or numerical study on intermediate-to-slender circular CFDATs.Here,a comprehensive numerical study was conducted on a modeling method for the first time to simulate the axial behavior of a slender circular CFDAT.This study outlines the development of numerical modeling techniques and presents a series of comparative studies using various material nonlinearities,confinement effects,and nonlinearity of the initial geometric imperfections for a slender column.The numerical results were compared with more than 80 previously available stub and slender experimental test results for verification.It was confirmed that the proposed numerical technique was reliable and accurate for simulating the axial behavior of intermediate and slender circular CFDAT.Furthermore,a parametric study was conducted to investigate the effects of geometric and material properties on the axial capacity of the CFDAT.Additionally,the slenderness and strength-to-width ratio of CFDAT were compared with those of concrete-filled double-skin steel tubular columns(CFDST).The simulated axial strengths were compared with those predicted using AS 5100 and AISC 360.New design equations for the CFDATs should be proposed based on AS 5100.
文摘The key role of the building envelope in achieving building energy efficiency and indoor comfort for the user has been long established.The most promising-and innovative-strategy for the building envelope of the future is based on a dynamic,active and integrated solution,that is able to optimize the thermal performance,integrate the active elements and systems,and exploit energy from renewable sources.This paper illustrates the most relevant results of a decade-long research activity carried out on active and integrated building envelopes at the Politecnico di Torino,in which numerical analyses and experimental campaigns,involving test cells and field monitoring,have been performed.The overall performances of different façade modules and the thermo-physical behaviour of various components,under different operating strategies,are presented and discussed.The analysis provides information on the contribution of each subsystem,e.g.glazing,sun-shading devices,natural and mechanical ventilation,...to the achieved energy efficiency and the overall performances of different typologies of Double-Skin Façades(DSFs)and Advanced Integrated Façades(AIFs).
基金supported by the National Science Foundation of China(Grant No.50329802).
文摘Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer(FRP)-concrete-steel double-skin tubular members(DSTMs).The strip method was used to calculate the section momentcurvature curves of the 3 specimens and 12 models.A theoretical formula is presented for the flexural strength of DSTMs.The test results show that the tension zone of the specimen FRP tubes was in hoop compression while the compression zone was in hoop tension.The load-carrying capacity did not decrease even when the mid-span deflection reached about 1/24 of the span length.The tests,simulation and theoretical analysis resulted in a simplified formula for the flexural strength of DSTMs and a tri-linear moment-curvature model was expressed as a function of the section bending stiffness for DSTMs.
文摘Various techniques for creating a comfortable thermal environment and saving energy have been proposed and employed in residential buildings in many countries, including Japan. For these techniques to be introduced, existing houses should be renovated. Among the techniques available, installation of additional inner windows is effective in creating a comfortable and energy-efficient living environment. In the present research, the effect of additional inner windows on the thermal environment and energy saving was investigated by measuring indoor climates. Windows were renovated in two rooms on the fourth floor of a four-story reinforced concrete building. Air temperatures, the humidity, the global solar radiation on horizontal and vertical surfaces, radiant temperatures, and the electricity consumption of air-conditioners were measured. A comparison of these vatues before and after the installation of inner- windows showed that the thermal environment and energy saving had improved. Results obtained from a thermal model agreed well with measured results by changing the value of solar transmittance and heat transmission coefficient of the glazing forlowing renovation. Furthermore, in a questionnaire survey conducted in summer, more than half of the occupants answered ＂cornfortabte＂ to a question on the overall thermal comfort.
基金supported by a DST project named“Development and performance analysis of Semi-Transparent Solar Photovoltaic double pane Window/Facade system”funded by the Department of Science and Technology,Government of India (TMD/CERI/BEE/2016/070(G)).
文摘Performance of Photovoltaic-double skin façade(Photovoltaic-DSF)system in summer has been critical.Owing to high solar ingress,cooling requirement of a building significantly increases.Photovoltaic-DSF system provides a shield and controls the heat gain through fenestration in the interior spaces.In the present article,mathematical correlations are developed for energy characterization of forced-ventilated Photovoltaic-DSF system in India’s hot summer zone i.e.Jaipur.The Photovoltaic-DSF system has been installed and monitored for Jaipur’s summer months(May to July).L25 Orthogonal array of design parameters(air cavity thickness,air velocity,and PV panel’s transparency)and their respective levels have been developed using Taguchi design to perform experiments.Based on experimental results,multiple linear regression has been used to forecast solar heat gain coefficient,PVs electrical power and daylighting illuminance indoors as function of design factors.The statistical significance of mathematical relationships is sorted by variance analysis,which is found to be in good accord with field measurements(R2>0.90).The proposed correlations are pragmatic in designing Photovoltaic-DSF systems for hot summer conditions.The Photovoltaic-DSF system with 30%transmittance and air velocity of 5 metres per second in 200 mm air cavity thickness achieved maximum energy performance in hot summers.
