The approach to daylighting by scale models and sun and sky simulators: A case study for different shading systems

At the Daylighting Laboratory of the Politecnico di Torino a facility, which consists of a sun simulator and a sky scanning simulator, allows daylighting simulations to be made inside scale models for both research and design purposes. Photometric data and digital images of the luminous environment are the results that are obtained. The "sky" covers one-sixth of the vault, while the "sun" is fixed: therefore the model is rotated to reproduce the entire vault and rotated and tilted to reproduce the relative sun-Earth position. In the paper the different components of the structure are shortly described, the possible fields of application are presented and, as an example of daylighting assessments, the results of a case study are reported. This latter is concerned with a comparative evaluation of different typologies of shading systems for South orientated facades for a sample high-school classroom: overhangs, external and internal + external light-shelves, horizontal fins are analysed, taking the effect of specular, semispecular and matt finishing also into account. For this purpose, reference conditions were assumed, both for sky conditions and sun positions, and repeated so as to compare environment performance which were obtained with the different shading systems. (C) 2007 Elsevier Ltd. All rights reserved.