modelling

Investigation the modelling of the mathematical model of expediency of project decisions of building materials including the human safety the asbestos. The asbestos is most widely used in the production of roof cover-slate. At this moment the building materials in which composition the asbestos is used, become the actual ecological and economical problem of the country.

Temperature and relative humidity have been measured in a BRE test house to investigate the vapour content in the void beneath the timber floor. The void can be ventilated naturally or by means of a fan supplying or extracting air. The results show that air flow into and out of the void is stack dominated. The fan needs to supply or extract large volumes of air in order to disrupt this. Measurements and modelling have shown that the vapour content in the void is generally dependent on the level in external air, and that the contribution from the ground is usually small by comparison.

Scale model experiments give possibilities for analyses of the design conceptions of ventilation especially of air distribution in large enclosures. When simulating aerodynamic and thermal processes in scale models of room ventilation, the flow patterns are visualised and the air flow temperature and velocity are measured. The paper presents the results of experimental tests of the air mean velocity field in three different size models of the same ventilated room. The field maps of the air velocity mean value were analysed.

Few detailed comparisons of modeled ad measured pollutant concentrations in multizonebuildings have been published. The COMIS air flow and contaminant transport modelpermits simulation of the effects of building and HVAC operation, as well as the influence ofthe local meteorology, on air flows within the building. We have recently used this model tosimulate the release of a gas-phase tracer in a three-story, multi-room building located atDugway Proving Ground, Utah, USA.

Since reduction of ventilation rates in dwellings for economical reasons, it has been necessary to study whether this reduction had not been done to the detriment of indoor air quality. Several means of investigating were developed: experimental tests are indispensable but usually expensive that is why numerous research centres choose to model the thermoconvective fields in rooms.

The overall objective of the present work is to evaluate the performance of three turbulence models, with a view to predicting characteristics of airflow within an anisothermic cavity. The standard K-c. model, the Renormalisation Group model (RNG) and the Reynolds stress model (RSM) are used in conjunction with the Fluent code. The accuracy and the relative performance of the three models are evaluated by comparing their numerical results with experimentally obtained data. This comparison is made for the constant flow rate of a twodimensional turbulent mixed convective airflow.

A simplified natural ventilation model for dwellings is developed and used to determine the impact of different ventilation strategies on the building loads and zones temperatures. It deals with the sensitivity of loads and temperatures to classical default parameters as : wind velocity, wind coefficient value, building environment and shielding conditions, and the actual cross section of the openings. All the simulations are performed using the TRNSYS 14.2 simulation software, TYPE56.

The work presented in this paper was done in 1997 as a final thesis in mechanical engineering, supervised by TRANSSOLAR Energietechnik GmbH in cooperation with the Institute for Thermodynamics and Heat Technology (ITW), University of Stuttgart. The contents of the work is the investigation of natural ventilation through window openings (single sided and cross ventilation) in an existing office space. Both measurements and computer simulation have been conducted.

Smoking restrictions in the workplace and increased health consciousness at home have seen a sizable reduction in the number of spaces where smoking is permissible. The aim of this study was to investigate the effects of ventilation in public houses, one of the few remaining public spaces where smoking is still socially acceptable. Little is known about the situation with shared occupancies, where relatively large areas are intended to accommodate both smokers and non-smokers.

Rooms with high windows are likely to have comfort problems caused by cold airdowndraught, which are usually solved by placing heating appliances underneath thewindows. In the city of Zug, Switzerland, a highly insulated educational building with aconcrete core system for heating and cooling is planned. The purpose of our investigation wasto find out whether any measures are necessary in this building to compensate the effects ofdowndraught in the occupied zone. Special attention has been paid to the effect of passivemeasures like air flow obstacles or openings in the window sill.