In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still rel...In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still relies mainly on experience and is incapable of quantifying the balance between the photovoltaic(PV)generation and the light requirements for agricultural production.As a result,actual PVGs are primarily PV-based,without carefully considering the needs of agricultural daylighting.To quantify the influence of the design parameters of PVGs and the layout of PV panels on the internal daylighting of serrated PVGs,and to optimize the daylighting design of the roof,this paper utilizes the Design Builder software to establish gradient models for a multi-span serrated-type PVG in tropical regions.Gradient models were established in terms of aspects,namely span,width of longitudinal/transverse daylighting strip,height,roof angle,and photovoltaic panel coverage rate(PCR).Daylighting in the greenhouse of each gradient model was simulated,and with the annual average daily light integral(A_(DLI))and distribution uniformity(DU)as evaluation indicators,the influence of various design parameters on the daylighting inside the greenhouse was quantified.The result reveals that:(1)PCR is the decisive indicator for daylighting in the PVG,and a function between PCR and the A_(DLI) is derived as A_(DLI)=-15.5 PCR+16.841;(2)Increasing the width of longitudinal daylighting strip significantly improves the A_(DLI) and enhances DU while increasing the span has a noticeable effect on improving A_(DLI) but does not significantly enhance DU;(3)Increasing the eave height without changing PCR does not enhance A_(DLI) but effectively improves DU;increasing the transverse daylighting strip and adjusting the roof angle hardly improves A_(DLI).In summary,it is recommended that the optimal span for PVGs in tropical regions be set within the range of 6.5-8.0m,and the eave height be set within the range of 2.5-3.5m.Preferably,the longitudinal daylighting strip with a width ranging from 0.5-0.8m should be installed.Based on the above relationship function,the PCR can be calculated according to the appropriate light demand for the cultivated crops.The daylighting design theory proposed in this paper can provide a theoretical basis and reference for the healthy development of the PV industry in tropical regions.展开更多
The following article has been retracted due to the fact that it cannot be accepted as Duplicate Publication. The Editorial Board takes a very strong respect to the author’s situation on this matter. This paper publi...The following article has been retracted due to the fact that it cannot be accepted as Duplicate Publication. The Editorial Board takes a very strong respect to the author’s situation on this matter. This paper published in Journal of Power and Energy Engineering Vol.3 No.4, April 2015, has been removed from this site.展开更多
Daylight is a fundamental element to obtain built environments that promote environmental comfort and energy efficiency. However, strategies that enhance the building daylight performance can affect its thermal energe...Daylight is a fundamental element to obtain built environments that promote environmental comfort and energy efficiency. However, strategies that enhance the building daylight performance can affect its thermal energetic performance. In this sense, research that addresses these aspects at the same time is considered essential. The objective of this paper was to evaluate the daylighting and thermal-energetic performance of administrative environments in a public institution, and to propose strategies that will enhance the use of daylight and lower energy consumption. Therefore, for future projects, and considering new buildings, and retrofit, this research will be an important reference. The research was developed through a case study of an administrative building model, in which the characteristics of solar orientation, light shelf use, glass type, and light and dark colors in walls were modified and combined, deriving it into models proposed. The daylighting performance evaluations were performed through dynamic simulation with the Rhinoceros for Diva software, and the thermal-energetic performance evaluations with the EnergyPlus software. The results of the work showed that a suitable solar orientation has a great impact on the automation of daylight and the energy consumption of the evaluated models, followed by the type of glass and the use of the light colors in internal walls, and that the use of artificial lighting with dimerization is fundamental as a complement to the daylight autonomy. For the boundary conditions of the study, the use of light shelves modified neither the daylight performance nor the thermal-energetic performance of the evaluated models.展开更多
Daylighting studies in buildings are key parts of environmental analysis and can be easily conducted at the early stages of design as part of environmentally responsive building design as well as to inform the final a...Daylighting studies in buildings are key parts of environmental analysis and can be easily conducted at the early stages of design as part of environmentally responsive building design as well as to inform the final architectural layout and interior design. The main aim of this study is to demonstrate how such daylighting studies can be completed at the early stages of design and, at the same time, to show the impact of window design and positioning on building indoor environments. The paper is focused on a study of window influence on room daylighting in residential buildings and computer lighting simulations in software packages： Windows Daylighting System and Autodesk Ecotect Analysis, have been carried out for different style and positioning of windows using several case studies. The main findings clearly indicated that not only the window size and style matters, but also the positioning of windows considering external walls which would make a significant influence on room daylighting levels and, therefore, such daylight studies are very important for the early stage of environmental analysis during building design.展开更多
Currently, daylighting ducts system is widely used as a daylighting device. Generally, daylighting duct system efficiently takes light from outside during the day, and conveys daylight to required location through lig...Currently, daylighting ducts system is widely used as a daylighting device. Generally, daylighting duct system efficiently takes light from outside during the day, and conveys daylight to required location through light duct manufactured by high reflectance mirror. Daylighting duct system can convey daylight to underground space that has no windows opening to external space. Daylighting system is composed of light collection part, light guide part and light emission part. Efficiency of daylighting system is depending on type of each part used in the system. However, it is very difficult to estimate exact light flow in the system considering type of the parts. Authors performed measurement experiments to make clear the light flow with real-size model and miniature model of daylighting duct system. We discussed effect of type of the parts on efficiency of daylighting duct system.展开更多
Different approaches have been introduced for the daylighting system to reduce energy consumption, but they were not populated due to complex, high cost, and insufficient designs. There has been a recent problem in ac...Different approaches have been introduced for the daylighting system to reduce energy consumption, but they were not populated due to complex, high cost, and insufficient designs. There has been a recent problem in achieving uniform distribution of sunlight at a destination deep inside the building. Therefore, we propose a system to achieve high illumination by illuminating the surface of the absorber (optical fibers) uniformly. To capture sunlight, parabolic reflector and Fresnel lens are used. Different reflectors and lenses are considered, compared, and investigated to direct uniform light, which solves the heat problem, into the optical fibers. In addition, this study includes comparison between fiber-based daylighting systems. The proposed system has been verified through simulation and experimental results.展开更多
The urgency of increasing energy efficiency in new building design and retrofits has pushed lighting simulation to play a central role in sustainable lighting design. The shape of the building and its orientation, the...The urgency of increasing energy efficiency in new building design and retrofits has pushed lighting simulation to play a central role in sustainable lighting design. The shape of the building and its orientation, the reflectances of building surfaces and glazed areas are important parameters in the daylighting design of buildings. Glazing systems can cut energy consumption and associated pollution sources, reduce peak demand, enhance daylighting performance and improve occupant comfort. This paper presents the results of a numerical and experimental comparison between the performances of an office building with and without external sunscreens. The aim was to analyse the illuminance distribution and some investigations have also been made with regards to the effect on daylight in rooms when sunscreens are used. The experimental results were obtained using an office building scale model and sky simulator. The numerical results were obtained through radiance, the ray-tracing program, to accurately predict the light levels and produce photo realistic images of the architectural space in all sky conditions： Illuminance values were obtained respectively through reference point measurements. The daylighting performances of the office building model with and without the sunscreens have been compared and analysed.展开更多
Improving daylighting strategy is a mandatory step to achieve visual enjoyment and energy saving in buildings. Psycho, physiological effects and energy performance have to be investigated in order to define a range of...Improving daylighting strategy is a mandatory step to achieve visual enjoyment and energy saving in buildings. Psycho, physiological effects and energy performance have to be investigated in order to define a range of different daylighting strategies, thanks to daylighting devices and climate based daylight modeling. Daylighting optimization ensures indoor healthier rooms, reduces electric light consumption and cuts the risk of glare. The best way to achieve these targets is to define users lighting needs, based on visual targets and to draw up some green measures to reduce electricity demands. Involving new climate-based daylight modeling metrics aims at defining proper illumination targets, in order to drastically reduce electrical lights, as well as reducing thermal loads deriving from cooling and HVAC （heating, ventilation and air conditioning） systems.展开更多
In the subtropical zone of China, a large number of old factory buildings rich in industrial historical and cultural value have been transformed into art studios. In the existing research on building renovation, there...In the subtropical zone of China, a large number of old factory buildings rich in industrial historical and cultural value have been transformed into art studios. In the existing research on building renovation, there are still problems such as insufficient lighting, low uniformity, and ignoring the effect of glare in the lighting environment of buildings after transformation. To fill this research gap, this paper provides a daylighting design strategy for these factory buildings in subtropical zones to ensure that the transformed art studios can offer an excellent indoor daylighting environment. Through the control variable method, the window-to-wall ratio, the form of external windows, and the visible light transmittance of glass are set with quantitative and variable values, and a design strategy that meets the requirements of international general daylighting standards is obtained step by step through the simulation. The daylight factor, uniformity, daylight autonomy, and dynamic glare probability are used in this research process to measure whether the daylighting strategy meets the daylighting requirements of the CIBSE Lighting Guide for art studios. The results show that the average indoor lighting coefficient can be increased from 1.29 to 6.18, and the minimum value of the lighting coefficient can be increased from 0.4 to 4.4 by enlarging the windowed wall ratio from 1:30 to 1:3, using the combination method of the horizontal window, skylight and skylight recommended by the analysis results, and selecting veneer glass with 88% transmittance. This allows for better uniform lighting inside the building and reduces glare. This conclusion can support the lighting performance design of industrial buildings in the future.展开更多
Although internal light shelves are more accessible and easier to maintain than external light shelves,they have lower daylighting efficiency than their external counterparts.Past studies on internal light shelves hav...Although internal light shelves are more accessible and easier to maintain than external light shelves,they have lower daylighting efficiency than their external counterparts.Past studies on internal light shelves have primarily focused on fixed room and window sizes rather than identifying them as factors that negatively impact the performance of the light shelves.This study assumes that the room ceiling height is a key factor affecting the daylighting performance of internal light shelves.It evaluates the performance of both internal and external light shelves under various ceiling heights to collect basic data for improving the daylighting performance of internal light shelves.The lighting simulation software Radiance was used to analyze the daylighting performance of these light shelves.The main findings are as follows:(1)In summer and midseason,internal light shelves should be installed in rooms with a ceiling height of at least 4.5 m to achieve a daylighting performance comparable to external light shelves.(2)In summer and midseason,internal light shelves enhance indoor uniformity ratios more than external light shelves;however,incorporating additional shading devices to achieve a comfortable visual environment with an indoor uniformity ratio of 0.3 or less is necessary.(3)Light shelves are not recommended in winter,because they do not contribute to a comfortable indoor lighting environment or energy savings for heating.Removable or detachable light shelves are advantageous;thus,internal light shelves are effective because they are relatively easy to remove and install.This study is significant,as it evaluates the effectiveness and applicability of internal light shelves based on varying ceiling heights.However,it did not consider other variables related to light shelves,indicating that further research is needed to dive into these aspects.展开更多
Accurate and rapid predictions of residential building performance are crucial for both new building designs and existing building renovations.This study develops an integrated prediction model using a stacking ensemb...Accurate and rapid predictions of residential building performance are crucial for both new building designs and existing building renovations.This study develops an integrated prediction model using a stacking ensemble learning algorithm to predict daylighting,thermal comfort,and energy consumption in residential buildings.The model incorporates multimodal residential building information as inputs,including image-based floorplans and vector-based building parameters.A comparative analysis is presented to evaluate the prediction performance of the proposed stacking ensemble learning algorithm against three base models:Resnet-50,Inception-V4,and Vision Transformer(ViT-32).The results indicated that the stacking ensemble learning algorithm outperforms the base models,reducing the mean absolute percentage error(MAPE)by 0.17%–1.94%and the coefficient of variation root mean square error(CV-RMSE)by 0.37%–2.06%for daylighting metrics;the MAPE by 0.63%–4.46%and the CV-RMSE by 0.62%–5.13%for thermal comfort metrics;the MAPE by 1.42%–6.43%and the CV-RMSE by 0.27%–5.09%for energy consumption metrics of the testing dataset.Further prediction error analyses also indicate that the stacking ensemble learning algorithm consistently yields smaller prediction errors across all performance metrics compared to the three base models.In addition,this study compares the stacking ensemble learning algorithm to traditional machine learning models in terms of prediction accuracy,robustness,and generalization ability,highlighting the advantages of the stacking ensemble learning algorithm with image-based inputs.The proposed stacking ensemble learning algorithm demonstrates superior accuracy,stability,and generalizability,offering valuable and practical design support for building design and renovation processes.展开更多
This paper explains how the optimized classrooms were selected and the results that were achieved by the optimizations carried out and finalized.The context of the research is the city of Concepción,in Chile.Virt...This paper explains how the optimized classrooms were selected and the results that were achieved by the optimizations carried out and finalized.The context of the research is the city of Concepción,in Chile.Virtual models of classrooms were evaluated using the Radiance software.We used a methodology that allowed us to determine the luminous conditions under different types of skies,seasons of the year and times of the day.The evaluation of the typologies was performed based on three defined criteria,in order to achieve the stated design objectives.We defined the optimal solutions for each orientation and,finally,we stated design recommendations for daylit classrooms to ensure the visual comfort of the students.These recommendations link all that found in the initial analysis with that found in the optimization stage.展开更多
Daylighting plays an eminent role in the performance of indoor environments and their occupants,thus necessitating the need to investigate daylight perception of potential occupants at early design stages.The present ...Daylighting plays an eminent role in the performance of indoor environments and their occupants,thus necessitating the need to investigate daylight perception of potential occupants at early design stages.The present study introduces an interactive approach to collect and visualize brightness perception of daylighting in a large-scale immersive virtual environment using a game engine as a daylight simulation tool.The developed system allows users to explore building models freely at different day times set in virtual reality and report their perceptions in real time.Following a validation study(N=36)to investigate the consistency of brightness perceptions in a real environment and its virtual replica,a set of 24 participants were recruited to use the system to report their brightness perception in a virtual model of a daylit art museum,through snapshotting the scenes where they perceive as one of the following in terms of daylighting:(very dark,dark,bright,or very bright).Using an output of 419 snapshots,a"Perceptual Light Map"(PLM)was developed to visualize the collective brightness perception of participants as a heat map.Subjective responses were found to be positively correlated with four daylight metrics,with the highest correlation to mean luminance and the lowest to luminance ratio.The findings of this exploratory study represent a step towards a user-oriented supplement tool to the existing quantitative daylight metrics,validating game engines’adequacy as a daylight simulation tool,and illustrating the potentials of immersion and interaction principles for the perception of daylit spaces in virtual reality.展开更多
While the primary role of window attachments is often to moderate glare and solar heat gains,they are also able to provide additional daylight to interior spaces.For this purpose,a variety of daylight-redirecting wind...While the primary role of window attachments is often to moderate glare and solar heat gains,they are also able to provide additional daylight to interior spaces.For this purpose,a variety of daylight-redirecting window systems have been developed over the past 150 years.Fixed reflective systems(slats/light shelves)or prismatic systems that rely on total internal reflection work well under specific solar conditions,but generally sacrifice performance over a much wider range of incident solar angles and sky conditions.Dynamic systems-typically reflective slats-are more responsive to sun angles but have not been able to achieve optimal performance for glare and daylight redirection efficiency.A previous investigation into an adjustable,reflective blind concept first conceived of in the late 1970s showed promise but was not reduced to practice due to lack of adequate simulation and analysis tools.In this paper,this concept is further developed and its energy and visual comfort performance evaluated for four mid-latitude,temperate climates using ray-tracing simulation techniques.Results indicate significant potential lighting energy savings when compared with conventional automated reflective blinds(2.1-4.9 kWh/(m^(2)·a),or 14%-42%,depending on climate and orientation)or,especially,manually-operated matte white Venetian blinds(1.4-7.9 kWh/(m^(2)·a),or 9%-54%,depending on climate and orientation),while maintaining acceptable or better visual comfort conditions throughout the interior space.展开更多
The assessment of the daylighting performance of a design solution is a complex task due to the changing nature of daylight.A few quantitative metrics are available to designers to assess such a performance,among them...The assessment of the daylighting performance of a design solution is a complex task due to the changing nature of daylight.A few quantitative metrics are available to designers to assess such a performance,among them are the mean hourly illuminance(MHI),the daylight factor(DF),the daylight autonomy(DA)and the useful daylight illuminance(UDI).Each of these metrics has a purpose,a set of criteria and limitations that affect the outcome of the evaluation.When to use one metric instead of another depends largely on the design goals to be achieved.Using Design Iterate Validate Adapt(DIVA)daylighting simulation program,we set out to examine the performance behavior of these four metrics with the changing dimensions of three shading devices:a horizontal overhang,a horizontal louver system,and a vertical fin system,and compare their performance behavior as the orientation changes of the window to which these devices are attached.The context is a typical classroom of a prototypical elementary school.Our results indicate that not all four metrics behave similarly as we vary the size of each shading device and as orientation changes.The lesson learned is that not all daylighting metrics lead to the same conclusions and that it is important to use the metric that corresponds to the specific goals and objectives of the design and of the daylighting solution.The UDI is the metric that leads to outcomes most different than the other three metrics investigated in this paper.展开更多
Space syntax involves a set of techniques for analyzing the spatial configurations of various spaces at building and urban scales.Religious spaces,such as prayer halls,are exam ples of buildings where observers experi...Space syntax involves a set of techniques for analyzing the spatial configurations of various spaces at building and urban scales.Religious spaces,such as prayer halls,are exam ples of buildings where observers experience space mostly from a single point of view.Furthermore,traditional space syntax is mainly used in the analysis of visibility and space cognition in terms of isovists and graph-based measures.The other aspects of space cognition,such as day lighting,artificial lighting,and glare,are carried in the isolation of the space syntax analysis.This paper proposes the scaling of the space syntax field for the inclusion of other parameters,such as daylighting,and integration of the associated performative measures to space syntax analysis of the mosque typology to aid in the studying of overall space cognition based on com fort and environmental parameters.We present a case study on a typical mosque layout using m ulti-objective optim ization.The analysis presented in the paper has im plications for the architectural designs of spaces with respect to glare m anagem ent and daylight potential.Moreover,it is unique and builds on our previous work for the exploration of comfort,visibility,and proximity thresholds for stationary observers.展开更多
It remains challenging to conduct an efficient dynamic façade design.In this article authors try to address this issue introducing the façade daylighting performance improvement(FDPI)indicator aimed to evalu...It remains challenging to conduct an efficient dynamic façade design.In this article authors try to address this issue introducing the façade daylighting performance improvement(FDPI)indicator aimed to evaluate the performance of a dynamic(adaptive)façade from its daylighting performance point of view.To illustrate the FDPI application the authors introduced the preliminary dynamic façade concept for an office building located in Tel Aviv(Hot-summer Mediterranean Climate Csa)with further shape modification based on the daylighting performance analysis compared to the three alternatives representative of different typologies of dynamic façades.Al Bahr,One Ocean and The University of Southern Denmark façade systems were simulated under the same weather and building conditions of the preliminary dynamic façade concept and were considered as a benchmark for the study.The final dynamic façade concept elaborated by the authors in the preliminary comparative workflow showed noticeable daylight performance improvement with respect to the case studies comparative scenarios.The FDPI metric allowed to estimate a daylighting performance improvement of 43%of the final dynamic façade concept over the case study dynamic façade that showed the best performance in the daylighting simulations.展开更多
This research looked to improve the daylighting performance of a shading device as a window component.The paper describes the development of the decision-making framework(DMF)for the selection and design of shading de...This research looked to improve the daylighting performance of a shading device as a window component.The paper describes the development of the decision-making framework(DMF)for the selection and design of shading devices based on daylighting.The DMF presents the process of analysis of the shading devices’daylighting performance in the selection of existing shading devices and in the design of new shading devices.The research determined the shading device daylighting performance measures(such as illuminance and daylight autonomy)as well as the variables that influence daylight performance.Interactions among the variables and the effects of these interactions on the shading device daylighting performance were explained and quantified in the DMF.The DMF also included ways of present-ing the results of testing the shading devices and the process of making the decision.A case study for three blind systems was performed to determine if the DMF provides a concept for the analysis of the daylighting performance of shading devices and for making decisions about the design/selection of the shading device.Computer simulation was used to calculate the illuminance levels and the daylight autonomies(DAs)as a result of the application of these blinds.The values of the DAs are compared for three blind systems to select the most appropriate sys-tem to be applied on a proposed building.The DMF based on daylighting can help building designers to select the most suitable shading device based on its daylighting performance,and can help shading device manufacturers in designing new shading devices with improved daylighting performance.FIGURE 2.Simplified DMF diagram.展开更多
Extensive documentation has been developed to support the benefits of daylight for building occupants.Recently,the high performance building industry has shown a trend towards prioritizing better daylighting condition...Extensive documentation has been developed to support the benefits of daylight for building occupants.Recently,the high performance building industry has shown a trend towards prioritizing better daylighting conditions.In response to this trend,the Leadership in Energy and Environmental Design(LEED)rating system now addresses daylighting and views as one of the criteria for compliance.However,effective daylighting has its challenges-most importantly addressing the issue of glare.This paper discusses the issue of glare and its relationship with requirements for effective daylighting within the criteria of the LEED rating system.In this study,a LEED certified building on Montana State University’s campus was considered as a case study.This paper conducts an analysis by comparing the results obtained from compliance procedures for LEED with independent evaluations of glare using simulation and post occupancy evaluation surveys.This paper concludes that the‘illuminance simulation’option provided in the current version of LEED(LEED v4)for compliance does not adequately address the issue of glare.This paper provides recommendations to improve the LEED rating system for indoor environmental quality which include:the incorporation of glare assessment in the evaluation procedures of daylighting and views;the use of dynamic simulations that incorporate climatic conditions in the evaluation of daylighting;and evaluating glare in early stages of design by using simulation tools.展开更多
基金2024 Science and Technology Commissioner Service Group's Emergency Science and Technology Research Project for Wind Disaster Relief in Hainan Province(ZDYF2024YJGG002-8)China Huaneng Group Co.,Ltd.Headquarters Technology Project,Optimization of Photovoltaic Vegetable Greenhouse Structure and Research on Planting Agronomy in Tropical Regions(HNKJ22-HF77)。
文摘In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still relies mainly on experience and is incapable of quantifying the balance between the photovoltaic(PV)generation and the light requirements for agricultural production.As a result,actual PVGs are primarily PV-based,without carefully considering the needs of agricultural daylighting.To quantify the influence of the design parameters of PVGs and the layout of PV panels on the internal daylighting of serrated PVGs,and to optimize the daylighting design of the roof,this paper utilizes the Design Builder software to establish gradient models for a multi-span serrated-type PVG in tropical regions.Gradient models were established in terms of aspects,namely span,width of longitudinal/transverse daylighting strip,height,roof angle,and photovoltaic panel coverage rate(PCR).Daylighting in the greenhouse of each gradient model was simulated,and with the annual average daily light integral(A_(DLI))and distribution uniformity(DU)as evaluation indicators,the influence of various design parameters on the daylighting inside the greenhouse was quantified.The result reveals that:(1)PCR is the decisive indicator for daylighting in the PVG,and a function between PCR and the A_(DLI) is derived as A_(DLI)=-15.5 PCR+16.841;(2)Increasing the width of longitudinal daylighting strip significantly improves the A_(DLI) and enhances DU while increasing the span has a noticeable effect on improving A_(DLI) but does not significantly enhance DU;(3)Increasing the eave height without changing PCR does not enhance A_(DLI) but effectively improves DU;increasing the transverse daylighting strip and adjusting the roof angle hardly improves A_(DLI).In summary,it is recommended that the optimal span for PVGs in tropical regions be set within the range of 6.5-8.0m,and the eave height be set within the range of 2.5-3.5m.Preferably,the longitudinal daylighting strip with a width ranging from 0.5-0.8m should be installed.Based on the above relationship function,the PCR can be calculated according to the appropriate light demand for the cultivated crops.The daylighting design theory proposed in this paper can provide a theoretical basis and reference for the healthy development of the PV industry in tropical regions.
文摘The following article has been retracted due to the fact that it cannot be accepted as Duplicate Publication. The Editorial Board takes a very strong respect to the author’s situation on this matter. This paper published in Journal of Power and Energy Engineering Vol.3 No.4, April 2015, has been removed from this site.
文摘Daylight is a fundamental element to obtain built environments that promote environmental comfort and energy efficiency. However, strategies that enhance the building daylight performance can affect its thermal energetic performance. In this sense, research that addresses these aspects at the same time is considered essential. The objective of this paper was to evaluate the daylighting and thermal-energetic performance of administrative environments in a public institution, and to propose strategies that will enhance the use of daylight and lower energy consumption. Therefore, for future projects, and considering new buildings, and retrofit, this research will be an important reference. The research was developed through a case study of an administrative building model, in which the characteristics of solar orientation, light shelf use, glass type, and light and dark colors in walls were modified and combined, deriving it into models proposed. The daylighting performance evaluations were performed through dynamic simulation with the Rhinoceros for Diva software, and the thermal-energetic performance evaluations with the EnergyPlus software. The results of the work showed that a suitable solar orientation has a great impact on the automation of daylight and the energy consumption of the evaluated models, followed by the type of glass and the use of the light colors in internal walls, and that the use of artificial lighting with dimerization is fundamental as a complement to the daylight autonomy. For the boundary conditions of the study, the use of light shelves modified neither the daylight performance nor the thermal-energetic performance of the evaluated models.
文摘Daylighting studies in buildings are key parts of environmental analysis and can be easily conducted at the early stages of design as part of environmentally responsive building design as well as to inform the final architectural layout and interior design. The main aim of this study is to demonstrate how such daylighting studies can be completed at the early stages of design and, at the same time, to show the impact of window design and positioning on building indoor environments. The paper is focused on a study of window influence on room daylighting in residential buildings and computer lighting simulations in software packages： Windows Daylighting System and Autodesk Ecotect Analysis, have been carried out for different style and positioning of windows using several case studies. The main findings clearly indicated that not only the window size and style matters, but also the positioning of windows considering external walls which would make a significant influence on room daylighting levels and, therefore, such daylight studies are very important for the early stage of environmental analysis during building design.
文摘Currently, daylighting ducts system is widely used as a daylighting device. Generally, daylighting duct system efficiently takes light from outside during the day, and conveys daylight to required location through light duct manufactured by high reflectance mirror. Daylighting duct system can convey daylight to underground space that has no windows opening to external space. Daylighting system is composed of light collection part, light guide part and light emission part. Efficiency of daylighting system is depending on type of each part used in the system. However, it is very difficult to estimate exact light flow in the system considering type of the parts. Authors performed measurement experiments to make clear the light flow with real-size model and miniature model of daylighting duct system. We discussed effect of type of the parts on efficiency of daylighting duct system.
文摘Different approaches have been introduced for the daylighting system to reduce energy consumption, but they were not populated due to complex, high cost, and insufficient designs. There has been a recent problem in achieving uniform distribution of sunlight at a destination deep inside the building. Therefore, we propose a system to achieve high illumination by illuminating the surface of the absorber (optical fibers) uniformly. To capture sunlight, parabolic reflector and Fresnel lens are used. Different reflectors and lenses are considered, compared, and investigated to direct uniform light, which solves the heat problem, into the optical fibers. In addition, this study includes comparison between fiber-based daylighting systems. The proposed system has been verified through simulation and experimental results.
文摘The urgency of increasing energy efficiency in new building design and retrofits has pushed lighting simulation to play a central role in sustainable lighting design. The shape of the building and its orientation, the reflectances of building surfaces and glazed areas are important parameters in the daylighting design of buildings. Glazing systems can cut energy consumption and associated pollution sources, reduce peak demand, enhance daylighting performance and improve occupant comfort. This paper presents the results of a numerical and experimental comparison between the performances of an office building with and without external sunscreens. The aim was to analyse the illuminance distribution and some investigations have also been made with regards to the effect on daylight in rooms when sunscreens are used. The experimental results were obtained using an office building scale model and sky simulator. The numerical results were obtained through radiance, the ray-tracing program, to accurately predict the light levels and produce photo realistic images of the architectural space in all sky conditions： Illuminance values were obtained respectively through reference point measurements. The daylighting performances of the office building model with and without the sunscreens have been compared and analysed.
文摘Improving daylighting strategy is a mandatory step to achieve visual enjoyment and energy saving in buildings. Psycho, physiological effects and energy performance have to be investigated in order to define a range of different daylighting strategies, thanks to daylighting devices and climate based daylight modeling. Daylighting optimization ensures indoor healthier rooms, reduces electric light consumption and cuts the risk of glare. The best way to achieve these targets is to define users lighting needs, based on visual targets and to draw up some green measures to reduce electricity demands. Involving new climate-based daylight modeling metrics aims at defining proper illumination targets, in order to drastically reduce electrical lights, as well as reducing thermal loads deriving from cooling and HVAC （heating, ventilation and air conditioning） systems.
文摘In the subtropical zone of China, a large number of old factory buildings rich in industrial historical and cultural value have been transformed into art studios. In the existing research on building renovation, there are still problems such as insufficient lighting, low uniformity, and ignoring the effect of glare in the lighting environment of buildings after transformation. To fill this research gap, this paper provides a daylighting design strategy for these factory buildings in subtropical zones to ensure that the transformed art studios can offer an excellent indoor daylighting environment. Through the control variable method, the window-to-wall ratio, the form of external windows, and the visible light transmittance of glass are set with quantitative and variable values, and a design strategy that meets the requirements of international general daylighting standards is obtained step by step through the simulation. The daylight factor, uniformity, daylight autonomy, and dynamic glare probability are used in this research process to measure whether the daylighting strategy meets the daylighting requirements of the CIBSE Lighting Guide for art studios. The results show that the average indoor lighting coefficient can be increased from 1.29 to 6.18, and the minimum value of the lighting coefficient can be increased from 0.4 to 4.4 by enlarging the windowed wall ratio from 1:30 to 1:3, using the combination method of the horizontal window, skylight and skylight recommended by the analysis results, and selecting veneer glass with 88% transmittance. This allows for better uniform lighting inside the building and reduces glare. This conclusion can support the lighting performance design of industrial buildings in the future.
基金funded by the Korean government(MSITRS-2023-00208303)supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)and the Ministry of Trade,Industry&Energy(MOTIE)of the Republic of Korea(No.RS-2024-00441860).
文摘Although internal light shelves are more accessible and easier to maintain than external light shelves,they have lower daylighting efficiency than their external counterparts.Past studies on internal light shelves have primarily focused on fixed room and window sizes rather than identifying them as factors that negatively impact the performance of the light shelves.This study assumes that the room ceiling height is a key factor affecting the daylighting performance of internal light shelves.It evaluates the performance of both internal and external light shelves under various ceiling heights to collect basic data for improving the daylighting performance of internal light shelves.The lighting simulation software Radiance was used to analyze the daylighting performance of these light shelves.The main findings are as follows:(1)In summer and midseason,internal light shelves should be installed in rooms with a ceiling height of at least 4.5 m to achieve a daylighting performance comparable to external light shelves.(2)In summer and midseason,internal light shelves enhance indoor uniformity ratios more than external light shelves;however,incorporating additional shading devices to achieve a comfortable visual environment with an indoor uniformity ratio of 0.3 or less is necessary.(3)Light shelves are not recommended in winter,because they do not contribute to a comfortable indoor lighting environment or energy savings for heating.Removable or detachable light shelves are advantageous;thus,internal light shelves are effective because they are relatively easy to remove and install.This study is significant,as it evaluates the effectiveness and applicability of internal light shelves based on varying ceiling heights.However,it did not consider other variables related to light shelves,indicating that further research is needed to dive into these aspects.
基金funded by the National Natural Science Foundation of China(52178017)the International Science and Technology Cooperation Fund Project(SJXTGJ2104).
文摘Accurate and rapid predictions of residential building performance are crucial for both new building designs and existing building renovations.This study develops an integrated prediction model using a stacking ensemble learning algorithm to predict daylighting,thermal comfort,and energy consumption in residential buildings.The model incorporates multimodal residential building information as inputs,including image-based floorplans and vector-based building parameters.A comparative analysis is presented to evaluate the prediction performance of the proposed stacking ensemble learning algorithm against three base models:Resnet-50,Inception-V4,and Vision Transformer(ViT-32).The results indicated that the stacking ensemble learning algorithm outperforms the base models,reducing the mean absolute percentage error(MAPE)by 0.17%–1.94%and the coefficient of variation root mean square error(CV-RMSE)by 0.37%–2.06%for daylighting metrics;the MAPE by 0.63%–4.46%and the CV-RMSE by 0.62%–5.13%for thermal comfort metrics;the MAPE by 1.42%–6.43%and the CV-RMSE by 0.27%–5.09%for energy consumption metrics of the testing dataset.Further prediction error analyses also indicate that the stacking ensemble learning algorithm consistently yields smaller prediction errors across all performance metrics compared to the three base models.In addition,this study compares the stacking ensemble learning algorithm to traditional machine learning models in terms of prediction accuracy,robustness,and generalization ability,highlighting the advantages of the stacking ensemble learning algorithm with image-based inputs.The proposed stacking ensemble learning algorithm demonstrates superior accuracy,stability,and generalizability,offering valuable and practical design support for building design and renovation processes.
文摘This paper explains how the optimized classrooms were selected and the results that were achieved by the optimizations carried out and finalized.The context of the research is the city of Concepción,in Chile.Virtual models of classrooms were evaluated using the Radiance software.We used a methodology that allowed us to determine the luminous conditions under different types of skies,seasons of the year and times of the day.The evaluation of the typologies was performed based on three defined criteria,in order to achieve the stated design objectives.We defined the optimal solutions for each orientation and,finally,we stated design recommendations for daylit classrooms to ensure the visual comfort of the students.These recommendations link all that found in the initial analysis with that found in the optimization stage.
文摘Daylighting plays an eminent role in the performance of indoor environments and their occupants,thus necessitating the need to investigate daylight perception of potential occupants at early design stages.The present study introduces an interactive approach to collect and visualize brightness perception of daylighting in a large-scale immersive virtual environment using a game engine as a daylight simulation tool.The developed system allows users to explore building models freely at different day times set in virtual reality and report their perceptions in real time.Following a validation study(N=36)to investigate the consistency of brightness perceptions in a real environment and its virtual replica,a set of 24 participants were recruited to use the system to report their brightness perception in a virtual model of a daylit art museum,through snapshotting the scenes where they perceive as one of the following in terms of daylighting:(very dark,dark,bright,or very bright).Using an output of 419 snapshots,a"Perceptual Light Map"(PLM)was developed to visualize the collective brightness perception of participants as a heat map.Subjective responses were found to be positively correlated with four daylight metrics,with the highest correlation to mean luminance and the lowest to luminance ratio.The findings of this exploratory study represent a step towards a user-oriented supplement tool to the existing quantitative daylight metrics,validating game engines’adequacy as a daylight simulation tool,and illustrating the potentials of immersion and interaction principles for the perception of daylit spaces in virtual reality.
基金supported by the California Energy Commission through its Electric Program Investment Charge(EPIC)Program on behalf of the citizens of California and by the Assistant Secretary for Energy Efficiency and Renewable Energy of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231.
文摘While the primary role of window attachments is often to moderate glare and solar heat gains,they are also able to provide additional daylight to interior spaces.For this purpose,a variety of daylight-redirecting window systems have been developed over the past 150 years.Fixed reflective systems(slats/light shelves)or prismatic systems that rely on total internal reflection work well under specific solar conditions,but generally sacrifice performance over a much wider range of incident solar angles and sky conditions.Dynamic systems-typically reflective slats-are more responsive to sun angles but have not been able to achieve optimal performance for glare and daylight redirection efficiency.A previous investigation into an adjustable,reflective blind concept first conceived of in the late 1970s showed promise but was not reduced to practice due to lack of adequate simulation and analysis tools.In this paper,this concept is further developed and its energy and visual comfort performance evaluated for four mid-latitude,temperate climates using ray-tracing simulation techniques.Results indicate significant potential lighting energy savings when compared with conventional automated reflective blinds(2.1-4.9 kWh/(m^(2)·a),or 14%-42%,depending on climate and orientation)or,especially,manually-operated matte white Venetian blinds(1.4-7.9 kWh/(m^(2)·a),or 9%-54%,depending on climate and orientation),while maintaining acceptable or better visual comfort conditions throughout the interior space.
文摘The assessment of the daylighting performance of a design solution is a complex task due to the changing nature of daylight.A few quantitative metrics are available to designers to assess such a performance,among them are the mean hourly illuminance(MHI),the daylight factor(DF),the daylight autonomy(DA)and the useful daylight illuminance(UDI).Each of these metrics has a purpose,a set of criteria and limitations that affect the outcome of the evaluation.When to use one metric instead of another depends largely on the design goals to be achieved.Using Design Iterate Validate Adapt(DIVA)daylighting simulation program,we set out to examine the performance behavior of these four metrics with the changing dimensions of three shading devices:a horizontal overhang,a horizontal louver system,and a vertical fin system,and compare their performance behavior as the orientation changes of the window to which these devices are attached.The context is a typical classroom of a prototypical elementary school.Our results indicate that not all four metrics behave similarly as we vary the size of each shading device and as orientation changes.The lesson learned is that not all daylighting metrics lead to the same conclusions and that it is important to use the metric that corresponds to the specific goals and objectives of the design and of the daylighting solution.The UDI is the metric that leads to outcomes most different than the other three metrics investigated in this paper.
文摘Space syntax involves a set of techniques for analyzing the spatial configurations of various spaces at building and urban scales.Religious spaces,such as prayer halls,are exam ples of buildings where observers experience space mostly from a single point of view.Furthermore,traditional space syntax is mainly used in the analysis of visibility and space cognition in terms of isovists and graph-based measures.The other aspects of space cognition,such as day lighting,artificial lighting,and glare,are carried in the isolation of the space syntax analysis.This paper proposes the scaling of the space syntax field for the inclusion of other parameters,such as daylighting,and integration of the associated performative measures to space syntax analysis of the mosque typology to aid in the studying of overall space cognition based on com fort and environmental parameters.We present a case study on a typical mosque layout using m ulti-objective optim ization.The analysis presented in the paper has im plications for the architectural designs of spaces with respect to glare m anagem ent and daylight potential.Moreover,it is unique and builds on our previous work for the exploration of comfort,visibility,and proximity thresholds for stationary observers.
基金the Ministry of Science and Higher Education of the Russian Federation as part of the World-class Research Center program:Advanced Digital Technologies(contract No.075-15-2022-311 dated 20 April 2022).
文摘It remains challenging to conduct an efficient dynamic façade design.In this article authors try to address this issue introducing the façade daylighting performance improvement(FDPI)indicator aimed to evaluate the performance of a dynamic(adaptive)façade from its daylighting performance point of view.To illustrate the FDPI application the authors introduced the preliminary dynamic façade concept for an office building located in Tel Aviv(Hot-summer Mediterranean Climate Csa)with further shape modification based on the daylighting performance analysis compared to the three alternatives representative of different typologies of dynamic façades.Al Bahr,One Ocean and The University of Southern Denmark façade systems were simulated under the same weather and building conditions of the preliminary dynamic façade concept and were considered as a benchmark for the study.The final dynamic façade concept elaborated by the authors in the preliminary comparative workflow showed noticeable daylight performance improvement with respect to the case studies comparative scenarios.The FDPI metric allowed to estimate a daylighting performance improvement of 43%of the final dynamic façade concept over the case study dynamic façade that showed the best performance in the daylighting simulations.
文摘This research looked to improve the daylighting performance of a shading device as a window component.The paper describes the development of the decision-making framework(DMF)for the selection and design of shading devices based on daylighting.The DMF presents the process of analysis of the shading devices’daylighting performance in the selection of existing shading devices and in the design of new shading devices.The research determined the shading device daylighting performance measures(such as illuminance and daylight autonomy)as well as the variables that influence daylight performance.Interactions among the variables and the effects of these interactions on the shading device daylighting performance were explained and quantified in the DMF.The DMF also included ways of present-ing the results of testing the shading devices and the process of making the decision.A case study for three blind systems was performed to determine if the DMF provides a concept for the analysis of the daylighting performance of shading devices and for making decisions about the design/selection of the shading device.Computer simulation was used to calculate the illuminance levels and the daylight autonomies(DAs)as a result of the application of these blinds.The values of the DAs are compared for three blind systems to select the most appropriate sys-tem to be applied on a proposed building.The DMF based on daylighting can help building designers to select the most suitable shading device based on its daylighting performance,and can help shading device manufacturers in designing new shading devices with improved daylighting performance.FIGURE 2.Simplified DMF diagram.
文摘Extensive documentation has been developed to support the benefits of daylight for building occupants.Recently,the high performance building industry has shown a trend towards prioritizing better daylighting conditions.In response to this trend,the Leadership in Energy and Environmental Design(LEED)rating system now addresses daylighting and views as one of the criteria for compliance.However,effective daylighting has its challenges-most importantly addressing the issue of glare.This paper discusses the issue of glare and its relationship with requirements for effective daylighting within the criteria of the LEED rating system.In this study,a LEED certified building on Montana State University’s campus was considered as a case study.This paper conducts an analysis by comparing the results obtained from compliance procedures for LEED with independent evaluations of glare using simulation and post occupancy evaluation surveys.This paper concludes that the‘illuminance simulation’option provided in the current version of LEED(LEED v4)for compliance does not adequately address the issue of glare.This paper provides recommendations to improve the LEED rating system for indoor environmental quality which include:the incorporation of glare assessment in the evaluation procedures of daylighting and views;the use of dynamic simulations that incorporate climatic conditions in the evaluation of daylighting;and evaluating glare in early stages of design by using simulation tools.
