Because of the lack of valid information regarding the influence of bends on the thermal and hydraulic performance of flues, a series of preliminary experiments were conducted using a full-scale Perspex rig. Analysis of the results and observations enabled the development of a methodology capable of determining the reduction of flow rate arising from the presence of bends. The analysis has also shown that existing quasi-steady-state methods used for the design of these flue systems are valid.
This project has studied a selection of 16 typical museums for antiquities in five Mediterranean countries and was partly funded by the JOULE III of the European Commission DG XII. Through an elaborate analysis and complete refurbishment of the Archaeological Museum of Delphi, the programme has provided an example for an innovative museum design based on present-day know-how.
Most indoor airflows are mixed convection. In order to simulate mixed convection accurately and efficiently, this paper uses a two-layer turbulence model. The two-layer model combines a one-equation model for near wall flow together with the standard k-E model for outer-wall flow. The model has been used to predict the mixed convection by displacement ventilation in an office. The computed results agree well with the corresponding airflow pattern and the distributions of air temperature , air velocity, air velocity fluctuation, and tracer-gas concentration.
Highly-glazed spaces are attractive in many ways (solar heating, aesthetics, etc.), however, their thermal behaviour remains difficult to predict. In such spaces, the assumptions or methods generally used in building thermal simulation tools - e.g. homogeneous air temperature in the room, simplified calculations of radiative heat transfer between walls, absence of airflow modelling within the room - do not seem appropriate. We have developed a new model (AIRGLAZE) to improve the prediction of the thermal behaviour of large highly glazed spaces.
Refuge floor is specially designed in high-rise buildings for the purpose of supplying a temporarily safe place for evacuees under emergency situations. The provision of such designated refuge floor is a prescriptive requirement in the fire code of Hong Kong. Such a provision appears to be desirable by the regulators as it relates to simple rules and has administrative convenience. In order to fulfill its function, the refuge floor should be a safe place for the evacuees.
Thermal comfort in ventilated spaces depends mainly on air temperature, air speed and turbulence intensity. Mean air speed is commonly measured with omnidirectional hot sphere sensors, whereas directionally sensitive measurement instruments and CFD-simulations normally give the mean velocity vector. The magnitude of the mean velocity vector in turbulent room air flows can be much lower than the mean air speed due to different time averaging processes. This paper studies the difference both experimentally and theoretically as a function of turbulence intensity.
The present work concerns the measurement and the computational fluid dynamics (CFD) modeling of buoyancy-driven air flow through a stairwell that connects the two individual floors of a residential building. A series of experiments was performed in order to study the mas and heal transfer between the two floors. Air flow rates through this stairwell were measured using a single tracer gas decay technique. The analysis of results provided relations which can predict the mass and heat flow rate as a function of the inter-zonal average temperature difference.
This work deals with experimental investigations on human reaction to local air movements of people in global thermal comfort, performing light activity. An analysis on draught risk was developed comparing the results with previous research findings on human response to draught. The intensity of air velocity, in terms of mean value and relative turbulence, was referred to the level at which normally clothed people could perceive and feel air movements behind the neck, in global neutral thermal condition.
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