Daylight Simulation

At present the kinetics is basic, but there is no doubt that research into the field of responsive building facades will continue, to find more sophisticated design and technical solutions. This research explores the possibilities of kinetic composition afforded by Origami different techniques using squared module. Origami and paper pleating techniques are one of the conceptual design approaches from which Kinetics can be developed. The paper examines the possibilities of different arrangements of folded modules to create environmental efficient kinetic morphed skins. The paper aims to achieve different Kinetic origami-based shading screens categorized by series of parameters to provide appropriate daylighting. The main tested parameters are the form of Origami folds, the module size and motion scenarios. Ten origami cases where explored first using conceptual folded paper maquette modules, then parametrically modelled and simulated at four times of the year, 21st of March, June, September and December, taken every hour of the working day.

Climate change and rising energy costs necessitate a shift in how buildings that efficiently provide comfort are envisioned. With initiatives now aiming at bringing energy simulation into the mainstream of environmental design, the applicability of state-ofthe- art simulations in formally non-constrained creative production needs to be re-evaluated. To this end, a teaching experiment that includes multidomain simulations as drivers into the early architectural design process has been conducted; Master of Architecture students create a community centre with low energy use and high daylight utilization, presented in case studies. Performance increases are achieved by making appropriate morphological choices only; form and energy are thus linked in a tectonic fashion. A novel designsimulation process model that acknowledges both creative and analytic thinking is derived and discussed in the context of on-going integration attempts.

Daylighting in tropical and sub-tropical climates presents a unique challenge that is generally not well understood by designers. In a sub-tropical region such as Brisbane, Australia the majority of the year comprises of sunny clear skies with few overcast days and as a consequence windows can easily become sources of overheating and glare. The main strategy in dealing with this issue is extensive shading on windows. However, this in turn prevents daylight penetration into buildings often causing an interior to appear gloomy and dark even though there is more than sufficient daylight available. As a result electric lighting is the main source of light, even during the day.

The aim of this thesis is to investigate the applicability of a novel image synthesis technique based on Monte Carlo particle transport to daylight simulation. Many materials used in daylight simulation are specifically designed to redirect light, and as such give rise to complex effects such as caustics. The photon map technique was chosen for its efficent handling of these effects. To assess its ability to produce physically correct results which can be applied to lighting simulation, a validation was carried out based on analytical case studies and on simple experimental setups. As prerequisite to validation, the photon map´s inherent bias/noise tradeoff is investigated. This tradeoff depends on the density estimate bandwidth used in the reconstruction of the illumination. The error analysis leads to the development of a bias compensating operator which adapts the bandwidth according to the estimated bias in the reconstructed illumination.

Recent studies show that sufficient daylighting in schools may significantly increase students’ academic performance, promote better health and provide energy savings. Although innovative daylighting systems can be used, the basic strategy should be first to provide enough daylight at the back of the space by means of simple design methods.
This article examines the forms of the classrooms in respect to daylighting performance. Several types of classrooms are analysed under overcast and sunny sky, taking into consideration the shape and the size of the room and the openings, as well as the reflectance of materials used as internal finishes. Also, cases with one or two-sided illumination sources are studied.
The criteria for the analysis and the evaluation are: a) the uniformity of daylight distribution (Daylight Factors achieved on the working level) and b) the luminance ratios in the field of view.
The research is based on the computer simulation programme RADIANCE.
The aim of the study is to investigate the daylighting performance of each classroom type. A special reference is also made to Athens’ climatic conditions.

ÖZET Yapılarda aydınlatma amacı ile harcanan elektrik enerjisi toplam enerjinin yaklaşık %40'ını oluşturmaktadır. Bu sebeple tasarıma günışığını dahil ederek enerji tasarrufu sağlamak ön plana çıkmaktadır. Aydınlatma tasarımcıları ve mimarlar günışığından daha fazla yararlanma görevini üstlenirken, geliştirecekleri tasarımların enerji verimliliği ile ilgili öngörülerde de bulunmalıdırlar. Günışığının içeriye daha fazla alınması ile planlandığı gibi aydınlatma açısından enerji tasarrufu yapılırken, CO2 salınımı azaltılıp, görsel konfor koşulları iyileştirilebilir. Buna karşılık doğru yapılmayan bir günışığı tasarımında termal konforsuzluklara neden olunup, soğutma yükü arttırılabilir ve/veya kamaşmaya sebep olunabilir. Böyle sonuçlara yol açmamak için, hangi günışığı sisteminin kullanılacağı seçilirken dikkatlice karar verilmelidir. Bu çalışma kapsamında, seçilen Yaşar Üniversitesi Kafeterya binasında çatı penceresi kullanma önerisini DIALux ve DesignBuilder simulasyon programları ile test edilmiştir. Her iki programın özellikleri kullanılarak bu önerinin yapıdaki enerji tüketimine nasıl bir etkisi olduğu değerlendirilmiştir. Çalışma sonunda elde edilen sonuçlar incelenerek örnek yapıda önerilen çatı penceresinin kullanımının enerji tüketimi açısından yarattığı değişim tartışılmıştır. ABSTRACT The share of electrical energy consumption for lighting in buildings is about 40% within the total consumption. Daylight integrated lighting solutions can significantly reduce energy consumptions. Lighting designers and architects are in charge of benefitting from daylight, so that they have to take some precautions and consider daylight in design period. Increasing daylight penetration may significantly save energy, reduce CO2 emissions, improve visual comfort and enhance the quality of the indoor environment. On the other hand if not properly designed, this may turn the tides by increasing cooling loads, affect thermal comfort or causing glare. Therefore, deciding on which daylight system to use is a very important issue. In this study skylight's impact on a case study will be analyzed using two softwares; DesignBuilder and DIALux. These softwares are capable of simulating and evaluating skylights systems in energy savings both in terms of lighting and thermal comfort. In order to see how using skylight effects energy consumption, Yaşar University's cafeteria building has been evaluated as a case study. The gathered simulations (by using DesignBuilder and DIALux) have been analyzed. At the end of the study, the effectiveness of the proposed skylight system was discussed by looking at the energy consumption results.

The building technology class “Parametric Design” simultaneously teaches thermal and daylight performance simulation to novice users, usually Master of Architecture students. Own buildings are created, analysed and geometrically modified during the design process, resulting in structures that are energetically pre-optimized. It is shown that energy demand and daylight utilization can be significantly improved while taking into account formal considerations. Departing from a design process model that gives preference to either engineering or design thinking, multi-modal decision-making is diagnosed to be mediated by hybrid or multivalent representations, necessitating a shift in how inter-domain design knowledge flows might be understood. Opposed to purely linear or iterative process assumptions, a fluent state model of interconnected domains of analytic inquiry is proposed.

The use of daylight as the primary light source is an integral part of sustainable buildings, because daylighting has been recognized as a useful source of energy savings and visual comfort in buildings. The quality and quantity of natural light entering a building depend on different factors. Daylighting features if not properly designed, will create a negative energy situation, and can cause visual discomfort. With advances in computer technology, the interior illumination level can be predicted during the design stage, and the impact of changes in design variables on the luminous environment can be evaluated via lighting simulation programs. This paper aims to develop an approach to achieving better daylighting for improved luminous environmental conditions in interiors, using computer generated simulation programs, and underlines an approach for decision-making, based on performance evaluation of features in architecture design studios of Bangladesh

This paper introduces a spatial thermal data mapping application developed in a building performance simulation (BPS) integrated design teaching context. Derived from design activity research and a novel process model, the tool, a plugin for the parametric modeler Grasshopper3d, allows the spatial display and analysis of temporally dynamic, multizone thermal simulation results in Rhinoceros3d models. A tool use case study that reduces an already efficient design’s heating/cooling/lighting energy use by 19% from 84 to 68 kWh/m2 serves to analyze core features, how they relate to interdisciplinary design and principles of information visualization. The peculiar demands of building science data display in architectural design are further discussed alongside the evaluation of the tool's cognition benefits through the case study analysis and a user survey.

The city of Cairo in Egypt, as it was inscribed on the world heritage list in 1997 under the title of " Islamic Cairo " , recognizing its absolutely unquestionable historical, archaeological and urbanistic importance, on the recommendation of the International Council for Monuments and Sites (ICOMOS). Historical Cairo proved over time to be one of the distinctive cities that contains a group of spatial relations, environmental and climatic solutions, which made its urban fabric and architectural compositions able to interact efficiently with climate and local environment. The aim of this paper is to evaluate the day lighting design strategies that made " Islamic Cairo " a distinctive sustainable environmental city, one day lighting strategy evaluated simultaneously in terms of indoor environmental quality; to reach the design criteria used by architects at that era. The performance of a historical building evaluated using computer simulation. This research process led to deriving a mathematical relation that link permitted day lighting with its accompanied thermal impact. The research findings led also to performative design guidelines, introducing a contemporary interpretation for using historical elements.

1 ABSTRACT The focus of this research is the enhancement of daylighting design in office buildings and the lowering of energy consumption. This study systematically explores and analyzes the visual performance of two different prototypical office layouts through the case studies selected in Tirana. The sensitivity of total energy use due to orientation, window area, glazing properties (U-value, visible transmittance), shading system is described. The research approach is conducted through lighting simulation software and face-to-face questionnaires. For each office building the actual conditions are firstly analyzed, and then, different other options are provided. The findings from this study provide evidence of the problems of daylight and artificial lighting problems and especially workers´performance difficulties related to lighting conditions. Thus, recommended solutions, which try to optimize daylighting design, to enhance workers´productivity and to lower energy consumption, are provided.

A generative grammar producing visual patterns for the south façade of a prototype sustainable house is presented. The patterns are produced through the activation of the electrochromic material that is applied on the windowpanes of the façade. The class of the performatively effective façade configurations is approached as a visual language and the productive (generation), combinatorial (enumeration) and performative (verification) attributes of this language are examined. Random, performance driven, patterns could supply sufficient interior daylight without acknowledging the visual
potential of façade pattern generation. The uniqueness of the chosen approach is that the shape grammar encodes the performative constraints pertaining to the generation of
façade patterns in a visual manner by associating principles of two-dimensional pattern generation to levels of illuminance.

A large number of the indigenous buildings in the UAE are used nowadays as museums. The purpose of this research is to investigate the daylighting performance in terms of museum lighting requirements via one of the most common daylighting systems found in the indigenous architecture of Dubai (latitude 25°N longitude 55°E); i.e., the traditional double panel window, Dreesheh. The study at the outset included several site visits to a number of traditional UAE museums to select a proper space with the system under study for investigation; and to specify how typical displays of these museums are classified. This helped to associate the total acceptable illuminance exposure limits to the specified classifications, based on IESNA recommendations. The Desktop RADIANCE 2.0 program (DR) was used to evaluate the lighting performance of the daylighting system under clear sky conditions. On-site measurements were conducted to find characteristics of the interior surfaces and validate the simulation accuracy. The difference between the actual measurements and the simulated ones was estimated as ±4%. The lighting performance issues examined by detailed simulations were direct sunlight, horizontal illuminance levels and artifact exposure, diversity and uniformity of illuminance, and contrasting luminances in the field of view. These parameters were compared to the standard values or recommended ranges specified in lighting codes and handbooks such as CIBSE and IESNA. The study revealed several potential problems with this kind of exhibit spaces that can lead to permanent damage of artifacts and occupants’ discomfort. Finally, it concluded with recommendations to improve these issues.

Retro-reflective coatings applied to blinds of reduced geometric complexity promise to provide view to the outside while effectively controlling solar gains and glare. To characterize the reflection characteristics of such coatings over the entire solar spectrum, a novel extension to a scanning gonio-photometer is developed. The extended instrument is tested and applied to measure a coating's Bidirectional Reflection Distribution Function including the region of the retro-reflected peak. The measured data-sets are compiled into a data-driven reflection model for the daylight simulation software Radiance. This model is applied to illustrate the coating's effect in a comparison to purely diffuse and specular surface finishes on geometrically identical, flat blinds. Daylight supply, the probability of glare, and solar gains are assessed for an exemplary, South-oriented office under sunny sky conditions. The results indicate the potential of the coating to effectively shade direct sun-light even if applied on blinds with minimalistic geometries. The modeling technique is shown to be a general means to replicate the irregular optical properties of the coating, which cannot be represented by the standard models in daylight simulation software.

Climate-based daylight simulation allows performance predictions for façade designs based on available climate data. Simulations based on daylight contribution coefficients coupled with models of sky luminance distribution make this tool available even in the design process. Metrics describing glare probability and the potential to substitute electrical lighting by daylight are applied and design proposals iteratively improved. The method is demonstrated on an existing building, the " Neubad Lucerne " , which is subject to design studies by students of architecture. Proposals to extend the two South-facing facades are developed, aiming at lower glare probability and optimized use of daylight to minimize electrical energy consumption for lighting. This paper shows: a) The different façade designs in photorealistic renderings. b) The quantitative analysis of useful daylight illuminance and daylight glare probability. c) A comparison of the designs according to the predicted daylight glare probability. Finally, It closes wih a comment on using climate-based simulation as a design tool.

Purpose:
This research aims to create a passive dynamic system with immediate responses to environmental conditions without needing an energy source to operate and reduce operation and maintenance costs. Design/Methodology/Approach:
There has been growing awareness in recent years of the energy consumption and interior environmental comfort of buildings. Substantial evaluation of the building envelope and indoor human experience is required to develop sustainable solutions, create a responsive system that enhances building performance and human comfort in terms of energy consumption and daylight quality. In this paper, a new proposed advanced integrated façade called a passive dynamic shading device (PDSD) is revealed. The system is designed to contribute to energy reduction, daylight availability, and view quality through its ability to change position and placement to respond and adapt to new climate conditions. The thermal expansion phenomenon was used in the actuation process, with heat-activated actuators that correspond to specific dry-bulb temperatures. This paper concisely demonstrates the functional mechanism and performance of the PDSD. Sophisticated energy and daylight simulations have been executed to distinguish between three case studies. Each case represents one architectural option: 1-without shading devices. 2-with conventional fix shading devices. 3-PDSD.
Findings:
The result shows the PDSD can efficiently reduce overall energy consumption by up to 50%, increase the amount and quality of daylight by up to 60% compared to fixed shading devices, and obstruct the view from the interior 22% of the year.
Originality/Value:
Unlike other dynamic façade system studies, in this study, the goal is to create a new passive system using the thermal expansion phenomenon and evaluate its effectiveness on energy reduction, daylight availability, and view quality.

This research study discusses the accuracy of 3dStudio Max Design software in simulating illuminance
distribution on pendentive dome mosque design. The case study is the Federal Territory Mosque in Kuala Lumpur,
Malaysia. The mosque has pendentive dome design similar to the design of the Ottoman mosques and Hagia
Sophia in Istanbul, Turkey. The accuracy level is evaluated based on comparisons between the predicted software
and the measured-on-site data on the illuminance distribution. Both field monitoring readings and computer
simulations of the mosque interior (prayer hall) were collected and data logged during the winter solstice, the day
when the sun was on a perimeter at its highest latitude at the Tropic of Capricorn (23° 26′ 16″ S) which occurred
on 21st December 2013. The illuminance level was measured at five locations inside the mosque. Result of this
study revealed similar readings between the measured on-field and predicted computer simulation data with small
marginal value difference. This study suggests acceptable accuracy readings provided by 3dStudio Max Design
software for lighting simulation.

This technical report documents the development of the RADIANCE photon mapping extension and its integration into the official RADIANCE 5.0 distribution. A number of new techniques are now supported for a more efficient daylight simulation workflow, notably support for data driven material models via the bsdf modifier, and ray coefficients for climate based daylight modelling using the rcontrib tool. This document focuses primarily on the implementation details of the photon mapping software in support of this new functionality.

With the growth of high data rate speed cellular communication systems (UMTS, GSM, WiFi, Bluetooth…), prediction of the electromagnetic propagation becomes a strategic stake and an active subject of research. To give fast realistic predictions of the field strength and delay spread in wireless mobile communication networks, SILICOM developed the SLC software (note), based on parallel 3D raytracing combined with GO/UTD theory [1]. This paper describes our solution and shows its application to WiFi hotspot study.

Indoor comfort, energy efficiency and outdoor comfort are critical factors for the design of sustainable, climate conscious and livable urban environments. Simulations tools are available to be used by architects and urban designers to improve the environmental performance of buildings and districts from the early stages of the design process. Building requirements, standards and metrics can be used efficiently to assess the simulation results and parametric design methodologies allow for finding optimal design solutions. The schools of architecture struggle to teach the students how to perform correctly simulations and how to integrated them in the design process. The reason lies in the separation of the courses in which simulations are taught, usually building technology courses, and architectural and urban design studio courses. This research presents method and outcomes of an urban design course taught by the author during which the students learned how to integrate architectural and urban design principles with simulations and analysis of results against standards and metrics through parametric design. The course succeeded
as well in increasing the awareness of the students about sustainable and climate conscious design.

Complex fenestration systems typically comprise co-planar, clear and scattering layers. As there are many ways to combine layers in fenestration systems, a common approach in building simulation is to store optical properties separate for each layer. System properties are then computed employing a fast matrix formalism, often based on a directional basis devised by JHKlems comprising 145 incident and 145 outgoing directions. While this low directional resolution is found sufficient to predict illuminance and solar gains, it is too coarse to replicate the effects of directionality in the generation of imagery. For increased accuracy, a modification of the matrix formalism is proposed. The tensor-tree format of RADIANCE, employing an algorithm subdividing the hemisphere at variable resolutions, replaces the directional basis. The utilization of the tensor-tree with interfaces to simulation software allows sharing and re-use of data. The light scattering properties of two exemplary fenestration systems as computed employing the matrix formalism at variable resolution show good accordance with the results of ray-tracing. Computation times are reduced to 0.4% to 2.5% compared to ray-tracing through co-planar layers. Imagery computed employing the method illustrates the effect of directional resolution. The method is supposed to foster research in the field of daylighting, as well as applications in planning and design.

An experimental study of photovoltachromic (PVCC) devices for dynamic solar control in buildings is presented. The fabricated devices underwent a complete opto-eletctrical characterization and the results obtained were employed as an input for the simulation of building integrated multifunctional windows. This multidisciplinary activity aims at achieving relevant feedbacks from the simulation of real large area devices in order to adjust and even direct further experimental efforts, before reaching the production phase. Devices having different electrochromic capacitances were used and the optical measurements became useful inputs for the simulation task. Simulation's results turned into feedbacks concerning the modulation of the transmittance spectra, the colour of bleached devices, the scale-up of PVCCs. Devices used in the current work showed a power peak of 4.22 mW/cm 2 at the maximum power point and a smart modulation of optical transmittance of 50.16% (at 700 nm). Simulations of natural light penetration in office buildings showed that the integration of PVCCs in traditional windows could dramatically increase indoor visual comfort. An increase of the average UDI for a typical room up to 71.8% and a decrease of intolerable glare levels (DGP higher than 0.45) down to 12% were the major benefits of the substitution of traditional clear glasses with integrated PVCCs.

Data-driven modelling provides a general means to represent optically complex fenestration in daylight simulation by its Bidirectional Scattering Distribution Function (BSDF). Radiance employs the tensor tree as a compact data structure to store the BSDF at high directional resolution. The application of such models under sunny sky conditions is, however, computationally demanding, since the density of stochastic backward samples must match the BSDF resolution. The bidirectional Photon Map is proposed to rapidly forward-sample the BSDF, starting from the known sun direction. Its exemplary application shows a potential speed-up of ≥ 98 % when compared to backward ray-tracing.

Daylight simulation software play a significant role in decision-making during the architectural design process. These software enable architects to make informed decisions about daylight performance in the early phases of the project. Radiance as a simulation engine provides a physically accurate model of the lighting conditions in the scene, thus capable of achieving a high degree of accuracy and validity. However, with a command line interface, it requires a large number of input parameters, which complicates modelling and restricts flexibility. When integrated in the early design process, this approach becomes less efficient, or requires enormous computation time. This paper introduces a daylight simulation software named DaylightX that uses the backward raytracing algorithm implemented on the GPU to calculate the spatial distribution of daylight across the space. The tool aims to enhance the capabilities of the simulation environments through a user-friendly interface and thus allow for flexibility in the design process. An individual residential unit-a shipping container-was used as a base case for evaluation. The modular design of shipping containers allows for flexibility in window placement and orientation, but requires careful design and implementation from daylight performance perspective. The results of the study can serve to improve the daylight performance of container housing units. Keywords daylight analysis, sustainable design, software development, computational design

Climate change and rising energy costs necessitate a shift in how buildings that efficiently provide comfort are envisioned. With initiatives now aiming at bringing energy simulation into the mainstream of environmental design, the applicability of state-ofthe-art simulations in formally non-constrained creative production needs to be re-evaluated. To this end, a teaching experiment that includes multidomain simulations as drivers into the early architectural design process has been conducted; Master of Architecture students create a community centre with low energy use and high daylight utilization, presented in case studies. Performance increases are achieved by making appropriate morphological choices only; form and energy are thus linked in a tectonic fashion. A novel designsimulation process model that acknowledges both creative and analytic thinking is derived and discussed in the context of on-going integration attempts.

Daylight can be considered as one of the most important principles of sustainable architecture. It is unfortunate that this is neglected by designers in Tehran, a city that benefits from a significant amount of daylight and many clear sunny days during the year. Using a daylight controller system increases space natural light quality and decreases building lighting consumption by 60%. It also affects building thermal behavior, because most of them operate as shading. The light shelf is one of the passive systems for controlling daylight, mostly used with shading and installed in the upper half of the windows above eye level. The influence of light shelf parameters, such as its dimensions, shelf rotation angle and orientation on daylight efficiency and visual comfort in educational spaces is investigated in this article. Daylight simulation software and annual analysis based on climate information during space occupation hours were used. The results show that light shelf dimensions, as well as different orientations, especially in southern part, are influential in the distribution of natural light and visual comfort. At the southern orientation, increased light shelf dimensions result in an increase of the area of the work plane with suitable daylight levels by 2%-40% and a significant decrease in disturbing and intolerable glare hours.

The aim of this paper is to investigate the daylight performance in an Austro-Hungarian heritage building located in Banja Luka, Bosnia and Herzegovina. The building was originally used as a military headquarters and  was  later  reused  for  administration  and educational functions. The measurement of daylight  was  performed in a representative room-office in the building. The measurement results are discussed with respect to international standards and in relation to the specific architecture of the building. Furthermore, the simulation of the daylight performance was performed by using the Design Builder software.
Key words: daylight performance, heritage buildings, visual comfort, simulation

Window design plays an important role in achieving energy efficient buildings and in providing thermal comfort of building occupants. This paper investigates a newly developed aerogel window and the potential improvement on the comfort factors of an office in relation to daylighting. Improved comfort levels can impact on health and wellbeing of building occupants leading to knock on effects on absenteeism and productivity. A simulation tool was presently created that will easily enable comparison of different façade design and their impact on heat and light transmission and therefore enable optimisation. One of the most important aspects of the present work was comparing the performance of the newly developed aerogel window against the more traditional Argon-filled, coated double-glazing. Whereas the aerogel window provided an extremely low heat-loss index of 0.3W/m2K, the latter usually offered a centre-glazing U-value of 1.4W/m2K. On a like-with-like basis the daylight transmissio...

This research study discusses the accuracy of 3dStudio Max Design software in simulating illuminance distribution on pendentive dome mosque design. The case study is the Federal Territory Mosque in Kuala Lumpur, Malaysia. The mosque has pendentive dome design similar to the design of the Ottoman mosques and Hagia Sophia in Istanbul, Turkey. The accuracy level is evaluated based on comparisons between the predicted software and the measured-on-site data on the illuminance distribution. Both field monitoring readings and computer simulations of the mosque interior (prayer hall) were collected and data logged during the winter solstice, the day when the sun was on a perimeter at its highest latitude at the Tropic of Capricorn (23° 26′ 16″ S) which occurred on 21st December 2013. The illuminance level was measured at five locations inside the mosque. Result of this study revealed similar readings between the measured on-field and predicted computer simulation data with small marginal value difference. This study suggests acceptable accuracy readings provided by 3dStudio Max Design software for lighting simulation.