IBPSA1995

Air velocity and air temperature are, in large glazed spaces, very heterogeneous and time dependant. Indoor and outdoor thermal conditions, localized solar radiation effects and ventilation systems are the conditions for mixed convection situations which produce, in large enclosures, significant velocity and temperature gradients. In this paper we describe the numerical techniques and processes that enable us to take these three types of conditions into account.

This paper explores three significant software development requirements for making the transitionfrom standalone lighting simulation/analysis tools to simulation-based design aid tools. These requirements include specialized lighting simulation engines, facilitated methods for creating detailed simulatable building descriptions, and automated techniques for providing lighting design guidance. Initial computer implementations meant to address each of these requirements are discussed to further elaborate these requirements and to illustrate work-progress toward fulfilling them.

Multizone airflow modelling is used for IAQ analysis as well as evaluation of cooling potential in buildings. A detailed evaluation of the wind pressure distribution on the envelope of a building is important for multizone: airflow modelling. There are a number of variables affecting the pressure distribution around a building due to natural wind. Wall-averaged values of Cp usually do not match the accuracy required. for multizone: airflow models.

In this paper we review the basic concepts of the Neutral Model Format for component description, of the SPARK objet-based simulation environment, and present a translator from NMF to SPARK. The purpose of the above is to document the NMF claim that translation from NMF to any simulation environment is easy, and also get a feeling of the effort needed to obtain a workng translator. The translator presented handles most NMF constructs (equations, loops, sums, embedded controls) with the notable exception of events. Working examples of translator-generated code are then presented.

This paper deals with the model validation methodology used at the Gaz de France Research & Development Division. The primary emphasis is on the latest developments, concerning different statistical methods for model validation and diagnosis. The corresponding computer implementation is called DVM standing for "Diagnostic et Validation de Modles".

A comprehensive simulation model, based on the TRNSYS program, for the evaluation of thermalstorage system behaviour in building climatization is presented here. The algorithm is applied to the study of a typical office building in presence of an ice or water storage. Possible economic advantages are presented and analysed. The remarkable differences obtained with different plant options confirm the necessity of an accurate study and justify the use of comprehensive computer models.

Building performance evaluation requires accepted standards for comparison. Thermal comfort conditions are widely accepted. This is different for lighting issues: currently set standards are far from describing user comfort sensations. Since both natural and artificial lighting have significant impact on the total energy demand, future building performance evaluation will need to take this into account. Inclusion of daylight as an extremely variable light source makes it virtually impossible to perform subjective tests under reproducable test conditions.

The studies presented here aim at defining and setting out a calculation code allowing the prediction of outdoor ambient thermal quality. Designers of urban spaces are expecting more specialized information such as skilled rules which may be achieved by the presented code, at present in process of development. The physical system is identified as being representative of the urban network of an average town like Saint-Denis, Reunion Island (about 60 000 inhabitants). The calculation code, made up by assembling different models, describes the thermal behaviour of the physical system.

A new dynamic simulation model for buildings has been developed which emerges by itself as it receivesdata or signals from the building under consideration. The model exists in two forms: Software written for the PC Windows environment, and Hardware in the form of a silicon microchip. This paper describes the background of the mathematical model and compares the results of its simulations with those of a conventional simulation model, in both cases using data from monitoring of an existing building. New possibilities for the development of advanced control systems are discussed.

This paper describes an artificial neural network- (ANN) modeling approach forpredicting the energv anddemand savings resulting from energy conservation measure (ECM) retrofits in select buildings. Simulated data sequences were used to minimize the experimental uncertainty in the initial model, and to provide post period data for training. A university building was chosen to provide the data set for this study. The building was modeled and calibrated using the DOE-2.IE building energy analysis program.