IBPSA2009

This paper investigates the impact of well geometry and surface reflectance on vertical daylight levels in atria with square forms under a CIE standard overcast sky. By reviewing some previous investigations and comparing with scale model measurements the vertical daylight factor calculated using Radiance are validated. More simulated vertical daylight factors for a very wide range of atrium geometries and reflectances are given. From the results the attenuation and distribution of the vertical daylight levels on the wall of a square atrium with different reflectances are displayed.

This paper demonstrates the use of High Dynamic Range (HDR) fisheye images of the sky dome in lighting simulations. The objective is to improve the accuracy of simulations with site specific sky conditions. The luminance information stored at a pixel level in an HDR photograph is used to light the simulated environment through an Image Based Rendering (IBR) technique.

This paper reports the simulation approach and prediction of annual energy performance of PV ventilated glazing systems with daylight saving as applying to typical office environment. Our computer model was developed via the ESP-r simulation platform in association with the RADIANCE lighting software. The new attempt of using indirect interaction between the two simulation programs through daylight coefficient, together with the coupled air-flow network and energy balance technique, has been proved very useful in tackling this kind of long period analysis.

In recent years, highly glazed atriums are favorable to architectural aesthetics and to taking advantage of daylighting and solar heating. However, t he estimation of the building load of an atrium building is difficult because of the complex thermal phenomena occurred in the atrium space. The study aims to find out the methods of conducting accurate simulations of the cooling loads of various types of atriums, using whole building energy simulation tool – EnergyPlus. Cases of atrium buildings are collected and classified into various categories.

Computational fluid dynamics (CFD) can provide detailed information of flow motion, temperature distributions and species dispersion in buildings. However, it may take hours or days, even weeks to simulate airflow in a building by using CFD on a single central processing unit (CPU) computer. Parallel computing on a multi-CPU supercomputer or computer cluster can reduce the computing time, but the cost for such high performance computing is prohibitive for many designers. Our paper introduces high performance parallel computing of the airflow simulations on a graphics processing unit (GPU).

Advanced natural ventilation (ANV), often characterised by the use of dedicated ventilation stacks, shafts and other architecture features such as atria, light wells, has gained popularity for natural ventilation design in recent decades. In this research, a prototype ANV system is proposed, and the likely thermal performance in a range of UK climatic conditions predicted using dynamic thermal simulation.

The aim of this paper is to present an automatic generator of zonal models that makes it possible to free the user from the choice of the specific flows models that have to be implemented in the zonal model and from the partitioning stage. The dynamic simulation tool called “O-Zone” is based on an advanced formulation of zonal models. It uses on a new way of sub-dividing the room that allows us to obtain a dynamic partitioning based on airflow patterns. The partitioning method chosen is the Octree method.

In the last years many building designers have turned their attention to natural ventilation, due to the potential benefits in terms of energy consumption related to ventilation and air-conditioning, especially in mild and moderate climates. Consequently, several calculation techniques have been developed to design and predict the performance of natural ventilation.  This article presents a review of the existing approaches to predict natural ventilation performance, including simple empirical models, nodal models (mono-zone and multi-zones), zonal models and CFD models.

The paper is concerned with the integration of building performance simulation within a collaborative/ multidisciplinary higher-education environment. The paper presents a semester-long setup in which a course attended by both architecture and engineering students and jointly taught by an architect and an engineer ultimately collaborate with an undergraduate architecture design studio on proposing upgrades to an existing building.

A wide range of scientifically validated Building Performance Simulation tools BPS is available internationally. The users of those tools are mainly researchers, physicists and experts who value empirical validation, analytical verification and calibration of uncertainty as defined by e.g. BESTEST. However, literature and comparative surveys indicate that most architects who use BPS tools in design practice are much more concerned with the (1) Usability and Information Management (UIM) of interface and (2) the Integration of Intelligent design Knowledge-Base (IIKB).