English

We present in this paper the essential aspects of the S2 system. This is the  internet realization of SEMPER: An active, multi-domain, space-based, object oriented design environment for integrated building performance modeling. We begin with an overview of SEMPER principles. We then present the component based system architecture of S2, which makes use of the Common Object Request Broker Architecture (CORBA) for communication between components including our analysis applications (written in C++) and other S2 components (written in Java).

The paper outlines a two-year research program where Radiance was used in the conversion of Empress Place, a national monument in Singapore, into an Asian Civilisation Museum. The paper describes how the research team fine-tune the modeling and software set- tings to cope with some of the contextual issues of design. Inaddition, the paper discusses how Radiance could be used to aid the design of the building. One of the more difficult tasks the researchers faced was to model and validate some of the daylighting control devices that are part of the existing features of the build- ing.

Nowadays   architects   commonly   use   the   ‘coupled space concept’. Examples are mezzanines, half-open office spaces and exhibition rooms. Because  of  the need to meet acoustical standards, the need to predict sound pressure levels and reverberation times for this category of spaces is ever growing.The transmission of sound from one space to another depends on design decisions like position, shape and dimensions of each of the interconnected spaces and of the “gap” between the spaces.

The numerical model for the analysis of the combined convective-conductive heat transfer in the building components has been developed. Presented model is based on the partial differential equation for the two- dimensional steady-state heat transport caused by conduction and convection. The finite element method was used to obtain the numerical solution of the governing equation. The general finite element formulation was derived by means of the Petrov- Galerkin approach. The developed computer program was used to study one typical lightweight building wall  construction.

Building dynamic simulation has been available to building design engineers for some time. However steady state methods are still being used and these methods do not provide the information required for making informed decisions on the best design options. An existing high specification building designed using steady state methods is used to compare the HVAC plant sizes installed to the plant sizes that would have been required if building simulation methods had been used.

An evaluation method for life cycle energy (LCE) and CO2 (LCCO2) of houses by the  system dynamics (SD), a method for understanding how all the objects in a system interact with one another, was presented. The building design strategies to predict and reduce the environmental loads for the several types of construction and building materials were investigated.

The paper discusses the technical features of the physically based computer simulation/visualization techniques for architectural lighting research. Potentials and limitations are evaluated in terms of input, algorithms, output, and analysis tools. The physically based simulation/visualization, supplemented with numeric information, is a promising tool for evaluating the luminous environment. The deficiencies are discussed to provide means of improving the usability and trustworthiness.

An indirect control technique using a single-zone space model is presented. The practice of adjusting temperature of heat supply medium inversely to outdoor air temperature (basic open-loop approach) was replaced with a flux control mechanism and facilitated with Takahashi algorithm1. In thismodel a coupling Laplace equation was applied with a noncapacitive nodal net of conductance and the hemisphere surface envelope concept in long-wave radiation calculations.

THERM is a freely available, user-friendly twodimensional heat transfer model for analyzing the impacts of thermal bridges in building components such as windows and doors. This paper begins by describing THERM as a tool for analyzing individual building components as well as envelope assemblies. The significance of THERM’s detailed radiation heat transfer model, which incorporates a view factor based radiation heat transfer algorithm, is then presented in detail.

Little work has been done on the closed loop response of refrigeration plant using the new chlorine-free refrigerants. A simulation model of a water-water refrigeration plant using R134a is developed for the purpose of investigating control system performance. The well-established problem of coupling between the two main regulatory control loops governing evaporator degree-of-superheat and plant capacity is recognised and the two control loops are tuned in harmony using an optimisation technique.