Roller Blinds Research Articles

Comprehensive evaluation of energy and indoor-PM2.5-exposure performance of residential window and roller blind control strategies

The window with a roller blind inside can have huge impacts on solar heat gains and the air exchange between indoor and outdoor environments, but its potential value in terms of improving both building energy efficiency and indoor air quality is poorly understood. This study examines cooling energy consumption and indoor PM2.5 exposure concentrations from indoor and outdoor sources in Hong Kong dwellings under seven different window and roller blind control strategies. Dwellings with windows facing south were simulated for a selected week in April using EnergyPlus. The modelled control strategies (including conventional rule-based control and Genetic-Algorithm-based predictive control) accounted for thermal comfort and indoor and outdoor environmental conditions. A novel coupled-window-and-interior-roller-blind zone was developed in EnergyPlus and used to capture the impact of shading on ventilation performance. Results indicate that dwellings under the predictive window and roller blind control strategy used 55% less cooling energy than those with windows closed and roller blinds open, while meeting the World Health Organisation standard for PM2.5 exposure (25 µg/m3). Comparisons between control strategies also show that shading windows (which were open) in the early morning led to an increase in cooling energy consumption, whilst opening windows at night and shading them with roller blinds in the first half of the night offered the co-benefits of cooling through increased ventilation and the ability to reduce indoor PM2.5 exposure.

Glare from Windows Assessment at Offices with Three Types of Internal Solar Shadings

Successful daylighting requires trade off and optimization between competing elements of façade, space, and lighting system. It also requires reliable tool for assessing the indoor visual comfort, especially discomfort glare from windows. The objective of the study was to investigate the users’ glare perception due to the use of internal solar shading systems by using laboratory experimentation with subjects and measurements. The purpose was to compare these results with a glare rating equation and Luminance Distribution Ratio (LDR) and to assess the reliability of this glare assessment tool to be used for assessing glare from window and in the context of humid tropics climate. The laboratory experimentations were conducted at three identical office rooms at the Department of Architecture of ITS in which each of the room’s windows was covered with different internal solar shading types e.i. Venetian, Horizontal, and Roller Blinds. Results showed good correlation between Luminance Distributions Ratio (LDR) with the users’ responses. Among the three internal shading, the Roller blind type had the highest correlation on both working activities and sitting positions to the glare perception as well as the fittest value complying the standard of luminance distribution. The research concluded that the Luminance Distribution Ratio method can be a reliable tool for assessing glare from window for many office situations in humid tropical climate.

Daylight glare mitigation by internal shading devices use and effects on building energy performance

Daylight glare arouses buildings’ occupants to insert internal shading devices. When solving glare issues, shading strategies can increase internal temperature and building cooling energy consumption, especially in hot climates. Indoor environmental quality has been treated through architectural and engineering projects utilising spatial-temporal metrics and controls algorithms. This article focused on investigating some interactions between user behaviour, shading devices proprieties, and their effects on building’s luminous and thermal environment. This research aimed to relate daylight glare probability’s reductions through internal shading devices uses, with their effects on the window’s solar heat gain and energy cooling demand. Using building modelling and simulation approach through Rhinoceros 3D 5.0 and plug-ins Grasshopper+DIVA, Daylight Glare Probability (DGP) hourly values were generated for an occupant, 1.5 m away from the window at a side lit-room. The open-access model is a typical private office in the multi-floors building. Window’s solar heat gains and energy cooling demands were recorded using EnergyPlus 8.4 software. The model was simulated in East, West, North and South orientations, at Florianópolis. Subtropical Brazilian city. Starting from ‘without solar control’ cases, 8 controls were applied to 4 internal shading devices: blinds 50°, blinds 0°, curtains and roller shades. Clearer and darker colours were considered by two proprieties sets. From two fixed obstruction modes (100% and 50%), DGPintolerable (>45%) and direct solar radiation (>50W/m²) were applied to proposed monthly, daily and automatic controls. DGPintolerable annual frequencies at uncontrolled condition varied from 30% to 65%. These differences pointed out design guidelines according to façades. It has been confirmed that 0° blinds don’t secure daylight glare and increase energy cooling demand. Dark roller shades, curtains and blinds 50° completely solved glare problems, controlled by ‘always 100% closed’ mode and DGPintolerable based controls. Clear devices still allowed 2% of DGPintolerable frequency. However, clear roller shades contributed to reducing annual cooling demand until 11.5% while other devices achieved until 52% increase. Dark curtains indicated maximum increased in annual window’s solar heat gain (3%). Obtained results allowed identifying some design guidelines to balance daylight glare protection and energy-efficiency, contributing to sustainable building design and low impact architecture.

A method to evaluate glare risk from operable fenestration systems throughout a year

Nowadays buildings are being designed with large glazed areas mainly due to aesthetics considerations but also to achieve daylit spaces. However, large glazed facades are prone to cause glare problems for building users. To mitigate this risk, it is important to predict existing glare metrics dynamically and reliably in the early stages of the design of a facade. Current evaluation methods for dynamic glare are either computationally too expensive or not suitable for operable façade systems. In this study, a new method is proposed to calculate the Daylight Glare Probability (DGP) index in a computationally efficient fashion, while allowing the fenestration system to switch states during the annual simulation. The method is based on a matrix formalism to calculate the vertical illuminance at a view position, and also on the calculation of a luminance map of the field of view solely from the direct component of the light sources. A first validation of the proposed method is presented. An office setup in Freiburg is monitored with a luminance camera for different weather conditions and different façade systems. Additionally, the calculation of the DGP index by the proposed method is compared with the calculation of the DGP by backward raytracing with high rendering parameters. The proposed method has been implemented in a building simulation program, called Fener. A case study is presented to illustrate the new possibilities offered by the Fener tool. The glare risk of three different textile roller blinds, with similar visible transmittance but different openness coefficient, is assessed.

A Simplified Approach for the Annual and Spatial Evaluation of the Comfort Classes of Daylight Glare Using Vertical Illuminances

A simplified approach to calculate the daylight glare comfort class (imperceptible, perceptible, disturbing, or intolerable glare) on annual basis and for a grid of points in a space is presented. This method relies on the calculation of the vertical illuminance (Ev) for each grid point only, which is compared to an Ev threshold value for each daylight glare comfort class. These Ev threshold values are determined through a comparison with the Daylight Glare Probability (DGP) values on an annual basis through a fault-detection technique, for a reduced number of points. Compared to an annual calculation of exact DGP values on a certain grid, this approach is able to evaluate the daylight glare comfort classes only, but it is less time consuming. The paper presents and critically discusses this simplified method by means of its application to different case-studies: south and west oriented office in Turin (Lat 45.1° N), in which the DGP is assessed for three points in the space, considering glazing with different transmission properties (specular or scattering) and visible transmittances, as well as three operable internal shading systems (one venetian blinds and two roller blinds, for solar or glare control). For the presented case studies, the average error in the classification of the space according to daylight glare comfort classes is below 5% when comparing this simplified approach to related DGP values.

Convection at the indoor side of complex fenestration systems: the ASHWAT model revisited

This paper examines the three-temperature problem of convection at the indoor side of a complex fenestration system (CFS) based on recent theoretical developments, namely the extended Newton formulation and the dQdT technique. CFD solutions were obtained for natural convection at the indoor side of various CFS configurations. The dQdT technique was then implemented numerically to obtain the paired heat transfer coefficients of each configuration. The results were used to assess the approximate relations used in the ASHRAE Window ATachment (ASHWAT) tool. The comparison shows that while there is remarkable agreement between the ASHWAT estimates and dQdT results for roller blinds, discrepancies exist between results for venetian blinds. Furthermore, although use of a delta resistor network to model convection at the indoor side is valid and relatively accurate for roller blinds, the application of this model to CFSs with venetian blinds requires additional levels of approximation. Nevertheless, the heat transfer rates calculated based on the approximate resistor-network model are in close agreement with the CFD results.

Smart lighting system using ANN-IMC for personalized lighting control and daylight harvesting

Lighting contributes a significant portion to the overall energy consumption in an office building. It is thus important to reduce the energy consumption of lighting systems especially for Net Zero Energy Buildings (NZEB). Maximizing daylight harvesting can significantly increase the energy savings. With increase in demand for satisfying occupant preferences in visual comfort, the need for personalized lighting in the office space is also rising. In this paper, a novel lighting control system for Net Zero Energy Buildings (NZEB) is proposed which models the lighting system using Artificial Neural Network (ANN) and utilizes this model with the Internal Model Control (IMC) principle for controller design. Modeling the lighting system using ANN reduces the challenge of modeling a large and complex system with inherent process variability without the need to analyze extensive data-sets. The proposed ANN-IMC controller uses feedback from sensors on the task table to maintain desired illuminance, is easy to tune with just one parameter and is robust to process variability. The proposed control design is applicable to square systems where the number of lights and number of sensors are equal. However, the proposed architecture can also be extended for controlling other lighting accessories such as roller blinds. The performance of the proposed lighting control system to harvest the daylight effectively is demonstrated using both simulation results and an experimental setup in test-bed environment. The versatility of the proposed system will allow an operator to deploy personalized lighting in an office space.

A systematic workflow for retrofitting office façades with large window-to-wall ratios based on automatic control and building simulations

Fully glazed façades are still preferred by many architects due to their aesthetic features. Although this choice offers opportunities for daylighting and view contact with the outside, it can lead to overheating and glare problems if climate is not taken into account in the design. This paper presents a workflow for retrofitting that can be applied to different office façades with large window-to-wall ratios. The workflow consists of analysing the space from the point of view of the functions of its façade and then applying a retrofitting strategy based on state-of-the-art building simulations and automated shading control. The proposed workflow is illustrated by a case study at an office in Malaga (Spain), in which the originally installed, manually-controlled interior vertical blinds are replaced with automatically controlled interior roller blinds with a metallized reflecting surface facing towards the glazing unit. A full optical characterization of the roller blinds is presented. A simulation-based control strategy is applied to the motorized roller blinds in order to maximize view contact with the outside and daylighting while controlling glare and overheating.

BRIGHTNESS PERFORMANCE OF OFFICE INTERIOR DUE TO ROOM’S WINDOW COMPONENTS CONFIGURATION

The paper reports room’s brightness performance of glass dominance office building facade in Jakarta due to the use of tinted and reflective type of glass wall and the combination of these with internal roller and venetian shading types. Method used to collect the data was mainly by direct measurements at three open-plan office buildings with different window components configurations under overcast sky condition, and at parallel sitting positions. Comparing the results of measurement with the standard of luminance value for office building was used as data analysis. Results show that the window components configuration influenced the luminance values of the interior and thus affected mostly on the brightness perception of the rooms. Both tinted and reflective glazing configured with roller blinds yielded accepted luminance value of rooms’ surfaces. They contributed to bright enough light perception of the rooms. On the other hand, the problem of room’s luminance values may occur with the use of reflective type of glass configured with the venetian blinds. The blinds exacerbated the daylight coming from window in which it resulted in significantly high average luminance value of the window.

Model-based predictive control of office window shades

In the automation of interior window shading devices, a control system that relies on a prediction of environmental conditions and a building's thermal response can provide savings to space-conditioning loads beyond what can be achieved using a reactive approach. The development of these control strategies can be difficult because of the uniqueness of each building. A simplified model-based predictive control (MPC) method for window shades is proposed. To this end, a control-oriented model representing the heat transfer problem in a perimeter office space was developed. The parameters of the model were estimated using the ensemble Kalman filter (EnKF). The energy-savings potential of the EnKF-based MPC approach for window shades was investigated using EnergyPlus simulations. This was accomplished by implementing the control-oriented model into the energy management system application of EnergyPlus. Simulations were conducted to assess the energy saving potential of using the EnKF-based MPC for roller blinds in a south-facing perimeter office space in Ottawa, Canada. The simulation-based results indicate the potential for about 35% reduction in electricity usage for space conditioning over manually operated interior roller blinds.

Lean Strategies for Window Retrofit of Italian Office Buildings: Impact on Energy Use, Thermal and Visual Comfort

The aim of this paper is to explore lean retrofit strategies for transparent envelope of existing Italian office buildings, to improve their performance and to ensure low energy use and a good thermal and visual comfort.Solar and light control is necessary to prevent overheating in office buildings those generally present high internal loads. The effectiveness of solar window films use in Italian buildings context is here investigated, in comparison with other strategies like the use of internal roller blinds and the substitution of the existing window panes with high performance ones. A sensitivity analysis was assessed to evaluate the office unit primary energy use under different retrofit solution, weather conditions and window to wall ratio. A conventional existing office unit was modeled in EnergyPlus and LBNL Radiance to assess heating, cooling and lighting energy demand coupled with visual comfort parameters. Thermal comfort was evaluated hourly in accordance with ISO 7730. The results are presented with a cost - benefit analysis to understand the best retrofit solution.

Asphalt Composites for Places with Higher and Atypical Load

Asphalt mixtures are less resistant to static load in comparison with a cement-concrete pavements. At traffic ways in logistic areas, weighted intersections, bus stops or climbing lanes can occur typical fault in the form of bruises, cross roller blinds or rut. This article deal with asphalt composites, which are known as materials, technologies, structural formations that can minimize this condition. In individual cases it is possible to use solid type VMT mix asphalt (mixture of high stiffness modulus), the technology of asphalt mixtures with fiber reinforcement, modification by natural asphalt binders, the use of polymer modified by binders or technology asphalt and cement concrete (ACC). Using ACC is despite the higher investment costs of these technology in specific cases preferable because of the less frequency and duration of repairs.

The Facilities Vegetables Warning and Control System Based on Mobile Phone SMS

The production of facilities vegetable significantly affected by environmental factors, therefore require real-time monitoring information of light, air temperature and humidity, soil temperature and humidity, and timely early warning and controlling, to prevent irreparable damage. This study achieved real-time monitoring and timely warning of environmental factors, and optimal control of pumps and roller blinds in the Facility vegetable. We have adopted Internet of Things technology and short message function in Mobile phone, the system through C # language and the SQL Server database to prepare. The application in Jilin Province Jinta Industrial (Group) Co.Ltd. shows that the system is better, achieved the purpose of high yield income. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

Facilities Vegetables Monitoring and Control System Design Based on WCF and Internet of Things

The production of facilities vegetable affected significantly by environmental factors, therefore it require real-time monitoring information of light, air temperature and humidity, soil temperature and humidity, and timely early warning and controlling, to prevent irreparable damage. This study achieved real-time monitoring and timely warning of environmental factors, and optimal control of pumps and roller blinds in the Facility vegetable. We have adopted Internet of Things technology and WCF communication interface, the system through C # language and the SQL Server database to prepare. The application in Jilin Province Jinta Industrial (Group) Co.Ltd. has showed that the system is better, achieved the purpose of high yield income.

Effect of the roller blinds on heat losses through a double-glazing window during heating season in Central Europe

Heat losses through window glazing are unavoidable but can be significantly suppressed during night hours using roller blinds. Results of calculations of the effect of roller blind on heat losses from central part of double-glazing window during the night in the heating season in Central Europe are presented. The hourly meteorological data for the outdoor air temperature, wind velocity and sky temperature are used. It is demonstrated that internal roller blinds can save about 33% and external roller blinds about 45% of heat losses through a central part of the double-glazing window at the blind to glass pane spacing above 20mm. The similar relative energy savings were obtained for the double-glazing window having low emissivity coatings, i.e. for the emissivity ɛ=0.20 the internal and external roller blind can save about 29% and 44% respectively.

Market Analysis of Textile Products Protecting Against UV Radiation (Used for Equipping Interiors, Construction and in Protective Clothing)

The aim of this article is to present the results of our analysis of the European market in the field of protective textile products, based on the EUROSTAT database and our own research. The market volumes of curtains and inner roller blinds, marquees and anti-solar curtains, male clothing accessories and female clothing accessories are presented and analyzed. Initial research of supply and demand in the Polish market of textile products protecting against UV radiation is also presented and discussed.

Solar and visible optical properties of glazing systems with venetian blinds: Numerical, experimental and blind control study

The increasing use of glazed areas in the building envelope can lead to high solar gains and glare problems that can strongly impact the entire building energy consumption, peak loads and indoor comfort. An important and fundamental strategy in sustainable building design for controlling solar heat gains and daylighting through fenestration is the use of shading devices. Therefore, it is recommended to use detailed models that can accurately estimate the optical properties of the different types of shading devices (such as roller blinds and venetian blinds) and include their effects in the glazing system analysis.This paper describes a net radiation method for determining both solar and visible optical properties of glazing with shading devices, particularly venetian blinds. Some numerical results were compared with in situ experimental measurements carried out in an outdoor test cell. The experimental work included the measurement of illuminance and irradiance fluxes and the determination of the visible and solar transmission properties of the fenestration system. The agreement between numerical predictions and experimental results was better for overcast than clear sky conditions. Moreover, a venetian blind control strategy that blocks direct solar radiation, whilst enabling the transmission of diffuse radiation to indoors, is implemented.

A context management system for a cost-efficient smart home platform

Abstract. This paper presents an overview of state-of-the-art architectures for integrating wireless sensor and actuators networks into the Future Internet. Furthermore, we will address advantages and disadvantages of the different architectures. With respect to these criteria, we develop a new architecture overcoming these weaknesses. Our system, called Smart Home Context Management System, will be used for intelligent home utilities, appliances, and electronics and includes physical, logical as well as network context sources within one concept. It considers important aspects and requirements of modern context management systems for smart X applications: plug and play as well as plug and trust capabilities, scalability, extensibility, security, and adaptability. As such, it is able to control roller blinds, heating systems as well as learn, for example, the user's taste w.r.t. to home entertainment (music, videos, etc.). Moreover, Smart Grid applications and Ambient Assisted Living (AAL) functions are applicable. With respect to AAL, we included an Emergency Handling function. It assures that emergency calls (police, ambulance or fire department) are processed appropriately. Our concept is based on a centralized Context Broker architecture, enhanced by a distributed Context Broker system. The goal of this concept is to develop a simple, low-priced, multi-functional, and save architecture affordable for everybody. Individual components of the architecture are well tested. Implementation and testing of the architecture as a whole is in progress.

The two‐dimensional cutting stock problem within the roller blind production process

In this article, we consider a two‐dimensional cutting stock problem encountered at a large manufacturer of window covering products. The problem occurs in the production process of made‐to‐measure roller blinds. We develop a solution method that takes into account the characteristics of the specific problem. In particular, we deal with the fact that fabrics may contain small defects that should end up with the waste. Comparison with previous practice shows significant waste reductions.

Optical models of complex fenestration systems

The need for energy conservation in buildings has spurred innovations in window technologies. These products include windows combined with shading devices, and windows featuring complex glazing such as switchable glazing, diffuse glazing, translucent and transparent insulation, patterned or decorative glass, etc. Current fenestration simulation tools for energy performance product ratings do not cover complex fenestration products. This paper addresses the development of detailed calculation models to compute the optical characteristics of complex fenestration products made up of a mixture of clear and scattering glazing layers. The models take into account not only the optical properties of the individual glazing layers making up the window product, but also the haze and gloss properties of the glazing layers. Specific optical models are developed to compute the optics of a clear substrate with applied or laminated scattering film, and composite film made up of a number of homogeneous materials with known optical properties. A general optical model was also developed for screen-like glazing panes such as insect/shading screens, roller blinds, drapery sheets, honeycomb transparent insulation and fibreglass translucent glazing.