Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can b...Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can be reduced by storing heat transmitted in phase change materials (PCM) as latent heat, in order to ensure a good situation of thermal comfort during all months of the year. In this work, thermal behavior of two roofing systems is studied. One roof is constituted only by usual materials in building. In the other, two phase change materials (PCM) are introduced according to three configurations. Study is interested to assess incorporation effect of two PCMs within the roof and to evaluate the optimum locations to reduce the energy consumption of air-conditioned room. Mono-dimensional numerical model validated analytically and experimentally, is used to carry out a parametric analyzes to determine characteristics of the layers in which the roofs are formed regardless of external climate effect. Numerical calculations are performed for three configurations of roof. Results show that insertion of phase change materials in roof provides best energy consumption saving regardless annual climate change. Generally, the three configurations lead to different results, depending on the combination of PCMs. This difference becomes less important when selection of PCMs take account the thermal comfort level and temperatures of hottest and coldest periods.展开更多
As socioeconomic development continues,the issue of building energy consumption has attracted significant attention,and improving the thermal insulation performance of buildings has become a crucial strategic measure....As socioeconomic development continues,the issue of building energy consumption has attracted significant attention,and improving the thermal insulation performance of buildings has become a crucial strategic measure.Simultaneously,the application of solid waste in insulation materials has also become a hot topic.This paper reviews the sources and classifications of solid waste,focusing on research progress in its application as insulation materials in the domains of daily life,agriculture,and industry.The research shows that incorporating household solid waste materials,such as waste glass,paper,and clothing scraps into cementitious thermal insulation can significantly reduce the thermal conductivity of the materials,leading to excellent thermal insulation properties.Insulation materials prepared from agricultural solid waste,such as barley straw,corn stalk,chicken feather,and date palm fibers,possess characteristics of lightweight and strong thermal insulation.Industrial solid waste,including waste tires,iron tailings,and coal bottom ash,can also be utilized in the preparation of insulation materials.These innovative applications not only have positive environmental significance by reducing waste emissions and resource consumption,but also provide efficient and sustainable insulation solutions for the construction industry.However,to further optimize the mix design and enhance the durability of insulation materials,continuous research is required to investigate the mechanisms through which solid waste impacts the performance of insulation materials.展开更多
From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship betw...From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.展开更多
Nowadays, rapid technological progress influences the dependability of equipments and also causes rapid obsolescence. The mechatronic and electronic equipment components are mostly affected by obsolescence. A new chal...Nowadays, rapid technological progress influences the dependability of equipments and also causes rapid obsolescence. The mechatronic and electronic equipment components are mostly affected by obsolescence. A new challenger unit possesses identical functionalities, but with higher performances. This work aims to find the optimal number of components which should be replaced by new-type units, under budgetary constraints. In this work, the new challenger unit is characterized by lower energy consumption and the optimization steps are based on genetic algorithm (GA). The result shows the importance of this type of replacement in order to economize energy consumption and to deal with obsolescence.展开更多
The influence of a polyvinyl chloride(PVC)-panel on the cooling load of a residential apartment in Mashad,Iran,is analyzed by the DeST-h software.And the summer natural ventilation of the residential apartment is in...The influence of a polyvinyl chloride(PVC)-panel on the cooling load of a residential apartment in Mashad,Iran,is analyzed by the DeST-h software.And the summer natural ventilation of the residential apartment is investigated to determine the wind speed into the apartment through the computational fluid dynamics software.The evaluation results of the indoor wind velocity show that most parts of the apartment are comfortable.The cooling load of the penthouse can be decreased about 10.5% or 6.5% when an air layer exists or does not exist between the ceiling and the PVC-panel,respectively,indicating that the existence of the air layer can decrease the cooling load.However,the effect of the increase in the air layer's thickness on the decrease in the cooling load is obvious.Adding a thin layer of air between the ceiling and the PVC-panel is a good step toward sustainable buildings.展开更多
The engineering community has been striving to design more sustainable buildings in an attempt to reduce both environmental impact and energy use during all phases of design,construction and operation.Design professio...The engineering community has been striving to design more sustainable buildings in an attempt to reduce both environmental impact and energy use during all phases of design,construction and operation.Design professionals currently have very limited guidance or tools to incorporate life-cycle and sustainability concepts into their designs.After reviewing the capabilities and limitations of four current life cycle analysis(LCA)computer programs,this research has selected the Athena Impact Estimator v4.0 to perform parametric studies of structural members made up of different construction materials.The energy consumption values are calculated and compared for columns,beams,concrete suspended slabs,precast double-tee sections and various other floor types.While Athena did offer some insights based on its LCA results,this research has concluded that existing LCA and sustainability analysis programs have too few options to meet the current needs of design professionals.A more accurate,sophisticated whole-building LCA tool needs to be developed to assess sustainable properties of design alternatives and to produce the most sustainable structural systems.展开更多
In this paper, the influence of different external wall insulation materials on the energy consumption of a newly built apartment in Germany is investigated. Three types of insulation materials commonly used in German...In this paper, the influence of different external wall insulation materials on the energy consumption of a newly built apartment in Germany is investigated. Three types of insulation materials commonly used in Germany including mineral fiber, polyurethane, and vacuum insula- tion panel are chosen for the case studies. An energy analysis model is established to clarify the primary energy use for production of the insulation materials and for building space heating. The calculation results show that the energy consumption for insulation material production increases with the insulation thickness, whereas the energy use for space heating decreases with the insulation thickness. Thus, there exists an optimum thickness to get the lowest total energy consumption for each kind of insulation material. The ascending order of the total energy consumption of the three materials is mineral fiber, polyurethane, and vacuum insulation panel. However, the optimum insulation thicknesses for the three insulation materials show a verse order at a certain heat transfer coefficient of the base envelope. The energy payback time (EPT) is proposed to calculate the payback time of the primary energy use for insulation material production. Mineral fiber has the shortest time, followed by poly- urethane and vacuum insulation panel. The EPTS is 10, 19 and 21 years, respectively when the heat transfer coefficient of the base envelope is 0.2 W/(m2.K). In addition, the simulated results show that the theoretical value and the simulated value are basically identical.展开更多
Polyvinylchloride(PVC)panel is one of the most favorite decorative materials that has been popularly applied as finishing of ceiling in residential buildings.It is about five years that the people incline to redecorat...Polyvinylchloride(PVC)panel is one of the most favorite decorative materials that has been popularly applied as finishing of ceiling in residential buildings.It is about five years that the people incline to redecorate the ceiling of old buildings with PVC panel in big cities of Iran,such as Mashad.In this study,the influence of ceiling PVC panel on the cooling and heating loads of studied apartment were determined by software DeST-h.In addition,the summer natural ventilation of the mentioned apartment is investigated by determining the wind speed into the apartment through the computational fluid dynamics(CFD)software.The evaluation of environment indoor wind velocity showed that most of the apartment space is a comfortable zone.The results of studied building analyses demonstrated that using PVC panel on the ceiling can decline the energy consumption of the penthouse(fifth level)of the investigated building,which is about 3.7%and 7%for studied methods of without and with air layer,respectively.In addition,although the existence of air layer can decline the cooling and heating loads,the increase in air layer thickness did not show significant decrease on building energy consumption.However,the PVC panel is expensive and is not suitable to be used for ceiling thermal insulation,but adding a thin layer of air between ceiling and PVC panel can be a good step toward sustainable building,when the people are inclined to utilize it as a decorative ceiling.展开更多
文摘Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can be reduced by storing heat transmitted in phase change materials (PCM) as latent heat, in order to ensure a good situation of thermal comfort during all months of the year. In this work, thermal behavior of two roofing systems is studied. One roof is constituted only by usual materials in building. In the other, two phase change materials (PCM) are introduced according to three configurations. Study is interested to assess incorporation effect of two PCMs within the roof and to evaluate the optimum locations to reduce the energy consumption of air-conditioned room. Mono-dimensional numerical model validated analytically and experimentally, is used to carry out a parametric analyzes to determine characteristics of the layers in which the roofs are formed regardless of external climate effect. Numerical calculations are performed for three configurations of roof. Results show that insertion of phase change materials in roof provides best energy consumption saving regardless annual climate change. Generally, the three configurations lead to different results, depending on the combination of PCMs. This difference becomes less important when selection of PCMs take account the thermal comfort level and temperatures of hottest and coldest periods.
基金funded by the National Natural Science Foundation of China (52078068)Postgraduate Research&Practice Innovation Program of Jiangsu Province (SJCX22_1391)+1 种基金the National Science Foundation of Jiangsu Province (BK20220626)Changzhou Leading Innovative Talent Introduction and Cultivation Project (CQ20210085).
文摘As socioeconomic development continues,the issue of building energy consumption has attracted significant attention,and improving the thermal insulation performance of buildings has become a crucial strategic measure.Simultaneously,the application of solid waste in insulation materials has also become a hot topic.This paper reviews the sources and classifications of solid waste,focusing on research progress in its application as insulation materials in the domains of daily life,agriculture,and industry.The research shows that incorporating household solid waste materials,such as waste glass,paper,and clothing scraps into cementitious thermal insulation can significantly reduce the thermal conductivity of the materials,leading to excellent thermal insulation properties.Insulation materials prepared from agricultural solid waste,such as barley straw,corn stalk,chicken feather,and date palm fibers,possess characteristics of lightweight and strong thermal insulation.Industrial solid waste,including waste tires,iron tailings,and coal bottom ash,can also be utilized in the preparation of insulation materials.These innovative applications not only have positive environmental significance by reducing waste emissions and resource consumption,but also provide efficient and sustainable insulation solutions for the construction industry.However,to further optimize the mix design and enhance the durability of insulation materials,continuous research is required to investigate the mechanisms through which solid waste impacts the performance of insulation materials.
基金Item Sponsored by National Basic Research Programof China (200002600)
文摘From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.
文摘Nowadays, rapid technological progress influences the dependability of equipments and also causes rapid obsolescence. The mechatronic and electronic equipment components are mostly affected by obsolescence. A new challenger unit possesses identical functionalities, but with higher performances. This work aims to find the optimal number of components which should be replaced by new-type units, under budgetary constraints. In this work, the new challenger unit is characterized by lower energy consumption and the optimization steps are based on genetic algorithm (GA). The result shows the importance of this type of replacement in order to economize energy consumption and to deal with obsolescence.
基金The Programme of Introducing Talents of Discipline to Universities(No.111-2-13)the Project of the State Key Laboratory of Subtropical Building Science of South China University of Technology(No.200833)
文摘The influence of a polyvinyl chloride(PVC)-panel on the cooling load of a residential apartment in Mashad,Iran,is analyzed by the DeST-h software.And the summer natural ventilation of the residential apartment is investigated to determine the wind speed into the apartment through the computational fluid dynamics software.The evaluation results of the indoor wind velocity show that most parts of the apartment are comfortable.The cooling load of the penthouse can be decreased about 10.5% or 6.5% when an air layer exists or does not exist between the ceiling and the PVC-panel,respectively,indicating that the existence of the air layer can decrease the cooling load.However,the effect of the increase in the air layer's thickness on the decrease in the cooling load is obvious.Adding a thin layer of air between the ceiling and the PVC-panel is a good step toward sustainable buildings.
文摘The engineering community has been striving to design more sustainable buildings in an attempt to reduce both environmental impact and energy use during all phases of design,construction and operation.Design professionals currently have very limited guidance or tools to incorporate life-cycle and sustainability concepts into their designs.After reviewing the capabilities and limitations of four current life cycle analysis(LCA)computer programs,this research has selected the Athena Impact Estimator v4.0 to perform parametric studies of structural members made up of different construction materials.The energy consumption values are calculated and compared for columns,beams,concrete suspended slabs,precast double-tee sections and various other floor types.While Athena did offer some insights based on its LCA results,this research has concluded that existing LCA and sustainability analysis programs have too few options to meet the current needs of design professionals.A more accurate,sophisticated whole-building LCA tool needs to be developed to assess sustainable properties of design alternatives and to produce the most sustainable structural systems.
基金This work was supported by the Natural Science Foundation of Tianjin, China (Grant No. 17JCZDJC31400) and the Scientific Special Commissioner of Tianjin, China (16JCTPJC52800).
文摘In this paper, the influence of different external wall insulation materials on the energy consumption of a newly built apartment in Germany is investigated. Three types of insulation materials commonly used in Germany including mineral fiber, polyurethane, and vacuum insula- tion panel are chosen for the case studies. An energy analysis model is established to clarify the primary energy use for production of the insulation materials and for building space heating. The calculation results show that the energy consumption for insulation material production increases with the insulation thickness, whereas the energy use for space heating decreases with the insulation thickness. Thus, there exists an optimum thickness to get the lowest total energy consumption for each kind of insulation material. The ascending order of the total energy consumption of the three materials is mineral fiber, polyurethane, and vacuum insulation panel. However, the optimum insulation thicknesses for the three insulation materials show a verse order at a certain heat transfer coefficient of the base envelope. The energy payback time (EPT) is proposed to calculate the payback time of the primary energy use for insulation material production. Mineral fiber has the shortest time, followed by poly- urethane and vacuum insulation panel. The EPTS is 10, 19 and 21 years, respectively when the heat transfer coefficient of the base envelope is 0.2 W/(m2.K). In addition, the simulated results show that the theoretical value and the simulated value are basically identical.
基金funded by the 111 Project(No.111-2-13)and the State Key Laboratory of Subtropical Building Science,South China University of Technology,China(No.200833)。
文摘Polyvinylchloride(PVC)panel is one of the most favorite decorative materials that has been popularly applied as finishing of ceiling in residential buildings.It is about five years that the people incline to redecorate the ceiling of old buildings with PVC panel in big cities of Iran,such as Mashad.In this study,the influence of ceiling PVC panel on the cooling and heating loads of studied apartment were determined by software DeST-h.In addition,the summer natural ventilation of the mentioned apartment is investigated by determining the wind speed into the apartment through the computational fluid dynamics(CFD)software.The evaluation of environment indoor wind velocity showed that most of the apartment space is a comfortable zone.The results of studied building analyses demonstrated that using PVC panel on the ceiling can decline the energy consumption of the penthouse(fifth level)of the investigated building,which is about 3.7%and 7%for studied methods of without and with air layer,respectively.In addition,although the existence of air layer can decline the cooling and heating loads,the increase in air layer thickness did not show significant decrease on building energy consumption.However,the PVC panel is expensive and is not suitable to be used for ceiling thermal insulation,but adding a thin layer of air between ceiling and PVC panel can be a good step toward sustainable building,when the people are inclined to utilize it as a decorative ceiling.