ventilation system

This study evaluated various ventilation strategies for efficiently removing house dust in the indoor environment. Experiments and simulations were performed to study the flow and diffusion fields that are affected by different locations and shapes of outlets. In this study, two kinds of ventilation strategies were considered i.e. ceiling exhaust and slit exhaust. In each case, experimental measurements showed that the characteristics of airflow within the whole room are generally similar except for airflow close to the outlet. CFD flow field and diffusion field simulations were also made.

The definition of a good indoor climate is important to the success of a passenger rail coach, not only because it will decide its energy consumption and thus influence its sustainability but also because good comfort for long journeys is essential. A survey in a coach investigating the thermal and air quality environment was undertaken. The intention is to use the results to optimise the control of the ventilation system to provide an indoor climate that passengers will find comfortable.

A methodology is presented for determining the air flow rate through a stack-ventilated single-spacedenclosure bearing a roof-mounted ventilation tower. We develop a "system discharge coefficient" which takes into account the pressure losses that occur at the intake opening of the enclosure, inside the tower and at the outlet opening. The system discharge coefficient is interpreted as a reduction in the area of the path that the air flow takes. Based on this reduced area the air flow rate is then determined.

One of the two air distribution systems serving the office rooms of a 25-year-old large office building was balanced in autumn 2002. The supply and extract air flow rates of 173 office rooms were measured before and after balancing. Before balancing, the air flow rates varied considerably from room to room and many of the office rooms were over pressurised. The average extract air flow rate in the whole of the building was 20.7 L/s.person and the standard deviation 11.0 L/s.person. The aim of the balancing process was to meet the design values dating from 1978.

Whether one considers the issues related to office workers’ well-being and productivity, or the issues from an energy and environmental perspective, there are clear evidences in favor of improving the quality of office built environment. This paper is con

Whether one considers the issues related to office workers’ well-being and productivity, or the issues from an energy and environmental perspective, there are clear evidences in favor of improving the quality of office built environment. This paper is con

With growing concerns about the impact of indoor environment quality on office workers’ well-being and productivity, coupled with the concern over the rising energy costs for space heating and cooling in office building sector, ventilation principles that

Indoor environmental quality (IEQ), subjective satisfaction of occupants and energy conservation ofbuildings are usually determined separately. Since the energy crisis in 1973, engineers haveendeavored to implement energy conservation in buildings. Unfortunately, the effort resulted in energysavings without the fundamental delivery of indoor satisfaction in many cases. It is worthwhile todetermine a balance strategy between the potential energy saving and occupants satisfaction inworkplaces.

Activated carbon filters have been used forpurification of air and water in industrialapplications. However these technologies have notbeen applied to the non-industrial builtenvironment in general and there is no standard toquantify or to classify the performance of thesesystems for in-duct mechanical systemapplication.

The design of ventilation equipment is important because it affects the ventilation performancedirectly. To improve the ventilation efficiency of the displacement ventilation, a new ventilation system was proposed in this study. The experiment was performed to measure the fume concentration and the visibility at four points under working conditions. In experimental results, the concentration of dust with a new ventilation system was decreased by about 42-60% compared to that of the existing system. The visibility was increased by about 11-18%.