English

Local exhaust ventilation systems are normally the most cost efficient method for controlling air pollutants and excessive heat. For many manual operations, capturing pollutants at or near their source is the only way to insure compliance with threshold limit values in the workers breathing zone. Local exhaust ventilation optimize ventilation airflow thus optimizing system costs especially where recirculation is not used.

Modeling of delivery efficiency was performed using three levels of combining measured and default input parameters and compared to measured data from seven manufactured homes. Using values based on all measured data provided modeled efficiency results that were closest to short-term coheat efficiency results. As individual measured parameters were replaced by estimated or default values suggested by the draft version of proposed ASH RAE Standard l 52P, the agreement with measured efficiency results worsened.

This study was initiated to determine the extent of cold temperature air leakage from operable windows available in todays marketplace and the impact that this has on the energy consumption of a house. During the heating season, changes in the window's leakage characteristics, as a result of thermal and pressure effects, were to be included. At two laboratories, air-leakage tests down to-30°C were performed on 35 windows, enough to reach some general conclusions about performance.

Finding a solution to the problem of draughty buildings can be fraught with difficulty. Very often only the symptoms are apparent and the root cause can be difficult to identify. All too often a 'try and see' approach is adopted until finally, if luck prevails, a successful solution is found. The design team addressing the problem of a draughty mall at a shopping centre in Shrewsbury adopted a different approach. The possible causes were identified using site knowledge and Computational Fluid Dynamics. A 'blind' analysis of site data was then undertaken by an independent statistician ie.

As experience with assisted naturally ventilated buildings has increased designers have extended the approach to larger and more demanding building types. This paper looks at two very different theatre projects where assisted natural ventilation systems have been designed, examines the design tools used, illustrates the solutions and shows how the built form was influenced.

Most building owners spend billions of dollars to outfit windows with drapes, shades, or blinds. Only a small fraction of this expenditure is ever targeted towards energy-efficient systems. Increased numbers of pleated, cellular shades with R-values presented In the R-3+ range are now in the marketplace. Foam plugs have been successfully used in many regions for low-cost, high R capability. The following elements shall be compared with respect to economic, utilitarian, thermal, and moisture issues:

The house is a system. The house is a system. The house is a system. It's becoming one of those phrases that is thrown about the construction world like overcooked pasta. But what does the phrase mean? Where does the system begin? Where does it end? What are the relationships between the components? And does It make any difference?

In the UK's temperate maritime climate, the need to air-condition a non-domestic building outside city centres should be the exception rather than the rule. Nevertheless, the potential clients for new or refurbished buildings, whether tenants or owner occupiers, are concerned about whether a non-air-conditioned building can deliver comfortable and productive working conditions, particularly in summertime.

Natural ventilation based on Passive-stacks are currently designed without incorporating heat recovery leading to wasteful heat loss. Heat recovery is not used because the pressure loss caused by conventional heat exchangers is large and could cause the ventilation system to fail. This paper presents laboratory investigation and computer simulation of a low pressure-loss heat recovery device for passive stack systems. It was found that the heat recovery effectiveness decreases with increasing stack velocity and heat recovery effectiveness of over 50% has been obtained in the experiments.