People employed in building offices have new needs in terms of comfort at the working place. To satisfy these needs, it is necessary that architects check carefully the efficiency of the corresponding new systems that they conceive in order to improve these people working conditions. This study shows that it is possible to optimize the sizing up of the different elements of an office cell front (envelope) containing, in addition to the glass wall, sun-breaker strips and an electrochromic protection. For that purpose, the inverse simulation technique was used thanks to several programs.
Various types of double façades can be distinguished. In earlier work a simple simulation model for the energy performance of double facades is developed. In this paper the problem of modelling a half-open sunshade between sheets is discussed. An extensiv
The optical performance of redirecting daylight materials under given outdoor illumination conditions is characterized by mean of virtual goniophotometry, and results are expressed as light source equivalent distributions that can be then used as input to daylighting simulations. Such a concept has been practically applied to the SerraGlaze product and will be extended with real case experiment.
In this paper we present a procedure to test software ability to describe daylight sources. The method will be applied to Lightscape release 3.2 [1]. The results have been achieved independently from the software developers comparing software results with analytical solutions. The tests deal with: a) definition of the algorithms used to represents different skies; b) influence of sun position; c) ground reflection management. Finally suggestions on how to use Lightscape in your daylight design are given.
In this paper, we use the validation test cases initialized within the subtask C, "Daylight design tools", of IEA SHC Task 21, "Daylight in buildings" to assess the accuracy of a commercial lighting software, Lightscape 3.2. We first analyzed the applicability and the limitations of the IEA 21 test cases, and we concluded some directives for validation test cases in order to guaranty its applicability to assess any lighting software.
In urban canyons reflected sunlight can play an important role in the illumination of buildings, particularly in orientations and during times of the day where sunlight is not incident on the windows. Facing buildings provide considerable obstruction to daylight by reducing the skylight contribution and sometimes blocking the access to sunlight. However, reflected sunlight is an important contribution to the internal illuminance of a room and should not be underestimated.
In this paper, we present the luminance calibration of the Coolpix 990, a digital camera made by Nikon. We test the different settings of the camera and choose which ones will be adapted to the calibration procedure. We characterize the projection resulting from the fish-eye lens made by Nikon for this camera. After this, the procedure and the experimental set-up used to calibrate it are detailed. We show how we used both an artificial sky and a sky luminance scanner to allow the calibration on the all EV (Exposure Value) scale.
We are developing a model that is able to predict the most adapted venetian blinds position (slat angle) for a VDU office worker, considering visual comfort matters. This algorithm, which takes into account room parameters as well as visual comfort criterions, is being validated by an in-situ measurement campaign. During 8 months, two field studies are lead to understand the way that office-workers actually use their blinds.
The aim of the present study is the proposal of a novel tracking mirror system for the daylighting of deep interior spaces, such as commercial buildings, underground railway stations, parkings, etc.. The analytical approach demonstrates that it is possible to supply an acceptable workplane illuminance for 6/8 hours per day during the year in southern Italy. The experimental data, obtained by means of a physical model, support the theoretical analysis. Benefits in terms of energy savings and illuminance level, especially in clear sky conditions, are outlined.
In December 2000, a new demonstration building for lighting research "Valotalo" (Light House) wasinaugurated at Helsinki University of Technology. The newest experimental technologies for integration of artificial and daylight were applied in order to validate their efficiency and peoples acceptance. Photovoltaic panels of 7 kW maximum power were integrated in the south faade. A 30 m2 solar heating system mounted on the roof of "Light House" produces warm service water. A daylighting test room is also built on the roof for further daylight research.