This paper considers the numerical modeling of room airflows and illustrates the usefulness of computational fluid dynamics as a design tool for ventilation systems. A computer code, which simulates steady, buoyant, turbulent, three-dimensional flows in Cartesian coordinates, was developed. The time-averaged equations for conservation of mass, momentum, and energy are solved. A low Reynolds number kE model is used to simulate the turbulent transport. The code was validated by comparing it to benchmark data for both liddriven and buoyancy-driven cavity flows.

The present Government has a target for reduction of the UK's carbon dioxide emissions of 20% of 1990 levels by the year 2010, which is in fact greater than the legal commitment set at the Kyoto summit on climate change in December 1997. Energy use in buildings accounts for approximately half of tl1e UK's annual carbon dioxide emissions and thus a reduction in the energy used in buildings is vital for this target to be achieved. A detailed knowledge of how energy is currently used is essential for assessing the potential for reducing the UK's C02 emissions.

This paper gives an account of a project to test the effectiveness of simple passive strategies to improve thermal comfort in Government Primary Schools in Pakistan .. Changes for improved thermal performance were carried out on five schools which were monitored both before and after modification. Schools are simple and minimally serviced. Improvements were controlled (as far as possible) to one strategy per classroom to make evaluation as straightforward as possible. An effectiveness score for a range of options has been developed.

This paper reports on the findings of a research exercise that has aimed to crystallise the current state of the Indoor Air Quality debate across a broad spectrum of the industry. The findings are discussed and conclusions drawn on whether there is evidence that the industry's efforts towards delivering good Indoor Air Quality is well received by building owners and operators in appreciable numbers

The large heat loss from Passive-stack ventilation (PSV) systems quite often makes natural ventilation systems unattractive and it is therefore desirable to implement heat recovery in PSV stacks. As the stackpressure is usually about a few Pascal, it is crucial that the heat recoveryunit used in a PSV system produces even lower pressure loss, which is extremely difficult to achieve with the conventional plate heat exchangers. This work is concerned with an a low pressure-loss heat recovery device based on heat pipes.

This paper gives an overview of the European NatVent® project on'Overcoming Technical Barriers to Low Energy Natural Ventilation in Office Type Buildings in Moderate and Cold Climates'. The project was targeted at countries like the UK with low winter and moderate summer temperatures where summer overheating from solar and internal gain can be significantly reduced by low-energy design and good natural ventilation.

Previous work by Linden, Lane-Serff and Smeed (1990) has developed a simple mathematical model for natural displacement ventilation of an enclosure. The work also introduced the experimental salt-bath technique, which uses salt solutions and fresh water to generate buoyancy forces that are analogous to those found in naturally ventilated buildings. The work claims that a good correlation exists between the predictions of the simple mathematical model and the results obtained using the salt-bath technique.

A concept design is proposed for a new generation of superstores, which addresses the global problem of Carbon Dioxide emissions and the demand of retail traders for increasing economies in energy. The new superstore building has been engineered from the ground up to incorporate the current best practice in environmental design. With application of suitable energy conservation technologies it is proposed that this approach will provide a retail environment fit for the next millem1ium and achieve a 50% reduction in Carbon Dioxide emissions over a conventional supermarket.