Object-oriented programming, equation-based submodels, and system reduction in SPANK

Collaborative efforts among building simulation researchers in Europe and the US have resulted in wide acceptance of certain features as necessary attributes of future simulation environments. As identified 'in the Energy Kernel System (EKS), the principal features are those of the object-oriented programming (OOP) paradigm, in which a hierarchy of submodels is readily defined and interconnected to form system models of widely varying purpose, solution methodology, and implementation description.

Multiple input transfer function model of ground heat transfer

The heat transfer processes occurring in the earth surrounding a building have a substantial effect on the building's energy consumption. During the heating season, for example, heat loss through ground- contact surfaces may be one of the most significant contributors to building heating load. Equipment sizing procedures and building energy analyses must use some method for calculating heat exchange between the building and the surrounding earth if they are to adequately calculate the building heating and cooling loads.

Modelling of thermal systems from technical sketches to equations

Modellers ands users of simulation softwares need to agree on a standard way to state the physical bases of their models The proposals presented in this paper are not new; they refer to the very classical way of describing thermodynamical systems. The basic piece of this description is the reference volume which may be "crossed" by mass and energy flows and which may also have some (mass and/or energy) "capacity". R-C networks are nothing more than "degenerate" or "simplified" sets of reference volumes.

Modelling heat, moisture and contaminant transport in buildings: toward a new generation software

This paper describes a general purpose software, Florida Software for Engineering Calculations (FSEC 1.1), that is capable of solving various transport equations used in building science (e.g., combined heat and moisture transfer, fluid flow, contaminant dispersion equations, etc.). The governing equations are solved by finite element methods. General capabilities and an overview of the software structure are given.

Model-based computer modelling: an approach for building energy simulation improvement

Many criticisms have been made about existing software for building energy analysis and simulation. In this paper, we try to show the interest of the model-based approach. The credibility of simulation results is pointed out. Main aspects of the CSTB contribution, in the framework of the GER ALMETH, are presented : the PROFORMA project about model documentation, and the MODELOTHEQUE project aiming to the design of a specific model base and its intelligent management system.

Luminance in computer-aided lighting design

Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems [Kaufman8l]. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system.

Indoor air quality simulation: IAQPC

The Indoor Air Quality Simulator for personal computers (IAQPC) has been developed in response to the growing need for quick, accurate predictions of indoor air contamination levels. Many building energy use programs are currently in use, but heating, ventilating, and air conditioning (HVAC) system designers need a way to determine if a planned system will ensure the health of building occupants. Scientists will find this program useful as an experimental design aid, and building personnel will be able to use it to determine approaches that will alleviate contamination problems.

Impact of interior lighting power reductions on commercial building energy use

Lighting energy conservation measures are typically recommended in commercial bui1ding energy audits. Over 60% of the cost in Bonneville Power's commercial building energy conservation programs are related to lighting. To estimate lighting energy savings it is not uncommon to ignore detailed energy simulations which account for interactions of lighting with heating and cooling systems and simply multiply hours of use by wattage reduction. This paper investigates the potential error in performing simplified 1ighting calculations which ignore interactions.

How good are single zone - monthly based - correlation methods for building energy and comfort performance assessment

Several single zone, monthly based, correlation methods have been developed at a national level , ver the past few years. Although the application limits of those methods are mostly unclear or unknown, the tendency grows to promote at the international level, such correlation methods as basis for simplified thermal calculations in the design process. The validity of a single zone, monthly based, correlation approach is analysed for residential building types in different european climate zones.

Evaluation procedures for building thermal simulation programs

This paper describes the techniques for validating dynamic thermal models devised by collaborating institutions in the United Kingdom. Following a review of past work on Imodel validation, the United States Solar Energy Research Institute (SERI) methodology was used as a starting point. Approximations and errors can arise at all stages of development, revision and use of a program. Emphasis was placed on thorough theoretical reviews of basic physical processes treated by programs and on the actual techniques adopted n some widely used programs.