An equation is developed for predicting the combined effect of naturally and mechanically induced air flows in buildings and solved by a combination of analytical and iterative methods. The resulting two-dimensional formulation, implemented as a simple computer program, allows rapid, hourly simulation of infiltration in domestic-scale buildings with a range of ventilation strategies.
The "step-down" tracer gas technique was used to evaluate experimentally in a mechanically ventilated test room the effect of varying thermal boundary conditions, inlet flow rates, and inlet - exhaust grids position on the Air Change Efficiency (ACE) values. The paper shows that the measured global ACE values are strongly correlated to the Archimedes number (Ar).
There are thousands of indoor ice rink arenas in the United States, Canada, and Europe. The combustion byproducts from the feel-powered ice resurfacing equipment are a potential health risk to both athletes and spectators. A field survey of ten ice rink arenas in Greater Boston and Halifax, Nova Scotia, indicates that the fuel type used by the resurfacer as well as the air exchange rate, the air distribution method, and the operation strategy of the ventilation system are significant contributing factors to the indoor air quality (JAQ) .
To develop guidance on effective ventilation strategies for buildings located in urban areas, it is necessary to have an understanding of the processes involved in the ingress of external pollution into buildings and its effect on indoor air quality. For naturally ventilated buildings, the combination of pressure forces and contaminant levels around the building is important in generating the level of internal contamination.
The Environmental Protection Agency's (EPA) ENERGY STAR® Homes program seeks to reduce greenhouse gas emissions by encouraging U.S. production home builders to voluntarily improve the thermal quality of their construction by minimizing infiltration, improving insulation, and right-sizing HV AC equipment. Tight homes need active ventilation to maintain indoor air quality, but mechanical ventilation increases initial home cost as well as operating costs.
The author maintains that the testing methodology of ASHRAE 62-1989R, mired in a swamp of controversy and "continuous maintenance," may need some fresh air.
Login