English

This paper discusses the use of the computer program DAYLIGHT, as a method of analysing and evaluating the natural lighting in buildings. The computer's design parameters and outputs are discussed in some detail, and the program is then used to examine some of the standard design criteria. The paper concludes with a case study of a primary school building to evaluate the accuracy and usefulness of the program.

Presently, the building performance analysis requires to take accuratly into account the coupling effects between building, HVAC and control. For large scale systems, this implies the intensive use of the simulation tools.Today, the existing tools are not flexible enough for this purpose. The present paper describes the development of a more adequate tool : CSTBt. This tool is built on the TRNSYS core (University of Madison), but offers a more adapted library of solvers and component models concerning the building envelope and the hot water heating network.

The simplified thermaI simulation of buiIdings is particularly useful for both bioclimatic design and the selection of the most suitable HVAC systems. The LEGO computer program was prepared in order to simulate the conventional HVAC plant-building systems and the complex systems Iike seasonal storage tank and solar collector plants. Therefore, it is possible with this kind of program to study the interaction among the various systems by means of combination of different simulation subroutines. In this way, a more accurate dimensioning of the systems can be achieved.

The model coupling problem (MCP) is a general non trivial problem raised by the universal choice of modularity as a conceptual base for object programming and search for efficiency in software tools development. Despite the apparent universality of the problem, it does not lead to a clear common formulation; on the contrary numerous "schools" of developers seem to dig gaps among the IBPSA community. We explore in this paper the origin of the misunderstanding, and propose a tentative conceptual tool aiming towards an international comprehensive articulation of BPSA projects.

Dimensioning programs for heating radiator networks are still today cumbersome to use. This project is trying to develope easy to use and fast calculation methods for the dimensioning and balancing of radiator networks. The main idea is to integrate the dimensioning and balancing program with the CAD software. Objectoriented programming and building product modelling methods are utilized in the prototype program.

CAD manufacturers are providing an increasing amount of integrated building design software. These integrated CAD systems have few, if any, facilities to assess building performance. The building design profession is increasing its use of performance assessment tools for traditional and refurbishment design and not just technologically advanced design. Performance assessment tools will continue to grow in importance as building technology moves towards providing Intelligent Buildings.

The simulation complexity of the thermal behaviour of buildings can be reduced by splitting it up as a hierarchical system of linked components. The behaviour of each component and its relations to the other components are modelled by an object oriented approach. We describe an Ada implementation of these concepts and a simple example of a multilayer wall at the end of this article.

From the observation that existing simulation programs exploit neither the subjacent parallelism in building energy management problems nor parallel computer possibilities, we develop certain principles and apply them to a well-known program, TRNSYS.

The current generation of building simulation software is based upon separate building, mechanical system, and equipment simulations. This scheme evolved primarily because of memory limitations of the computers which were used to develop the programs. Hardware advancements have eliminated some of these limitations so the separate building and system scheme needs to be reevaluated.

Increasing design standards within the building industry mean that some form of pre-construction testing of the building envelope is required. Expensive and time consuming field tests are becoming more impractical whereas the cost-effectiveness and greater flexibility of computer simulations will allow them to play an increasing role in building design. An expanding database of actual construction properties is needed to assist the use and advancement of existing models.