English

The paper discusses a methodology for thermal analysis applied to buildings in which the stochasticnature of the external forces is concerned. The considered forces are ambient temperature and solarradiation. The stochastic approach presented in this paper, consists in modelling the climatic inputs as a Markov process which have been injected on a reduced modal model describing the thermalbehaviour of the building.

For the conservation of an important museum collection in a historic building a better controlled indoor climate may be necessary. One of the most important factors is controlling relative humidity. Museum collections often are part of the interior of a historic building. In most cases the installation of an expensive air-conditioning system may cause damage to the building and its historic authenticity. Furthermore humidifying may lead to dramatic indoor air conditions with mould and condensation effects on the cold indoor surfaces or even internal condensation in the construction.

An Earth-to-Air Heat Exchanger (ETAHE) is a low energy cooling and heating technology for buildings. It uses the ground’s thermal storage capacity to dampen ambient air temperature oscillations by delivering outdoor air to indoor through a horizontally bu

The optimization of building thermal performance has traditionally been based on designers’ experience. However, optimization algorithms such as Genetic Algorithms (GA) have lately been used extensively in order to find the optimization configuration of a

The average air tightness of the ventilation ductwork in France is rather poor, corresponding toa 3A class. This is mainly due to air leakage in the fittings. Because of difficulties encounteredduring the implementation as lack of space, access problems or short time to proceed theinstallation, these fittings are not sealed enough, with mastic or adhesive tape.In order to limit this risk of leakage and to limit sealing operations on site, manufacturerspropose components equipped with joints. Some years ago, CETIAT has tested in itslaboratories different kind of such components.

The prediction of air infiltration is very important when simulating a building, due to the couplingaspects of the thermal and ventilation problem. So, the development of codes capable of performingsimple yet precise calculations is of great usefulness. Their utility can even be enlarged if we addsubroutines capable of air quality calculation and automation of some preliminary but necessaryassessments, like local pressure coefficients over the building facades and wind speed profiles.

A methodology for studying HVAC filter loading and subsequent microorganism removal is presented in this paper. First, the test facility used to challenge the filter media is discussed, then nine loading tests have been conducted , three for each of the three viruses, for the validation of the facility. Finally the results and conclusions are presented.

The aim of that experimental and modelling study is to determine the impact of different ventilation strategies on indoor particle concentration. For that experiment, polydispersed polyamide powders have been injected in a cubic test-room equipped with a mechanical ventilation system. Then experimental conditions have been simulated in a three dimensional numerical model. The results of the simulation have been compared with the experimental ones and it appears that the particle behaviour is well predicted.

For that study, a cross-sectional questionnaire survey was made : It concerned 2031 occupants of 11 naturally ventilated and 11 mechanically ventilated office buildings.The results of that questionnaire showed a strong need for improving IAQ, thermal comfort and reducing noise in open-plan offices. It appears that jobs that need a high degree of concentration or individual effort may not be suited for those open spaces.

Suppliers of heating, venting and air-conditioning products have leant on metalforming technology to pump out products that perform at higher levels of energy efficiency. In this paper three recent successes are presented of the leaders in that field :TRANE, RHEEM and YORK companies .