English

This paper discusses the numerical study of the effectiveness of atrium smoke exhaust systems. This study is part of a project initiated by A SH RAE and the National Research Council of Canada (NRCC), in which both physical and numerical techniques were employed to determine the effectiveness of such systems and to develop guidelines for their design. This paper presents numerical predictions obtained using a computational fluid dynamics (CFD) model and compares the numerical results with the experimental data obtained from tests performed in this project.

Canada Mortgage and Housing Corporation (CMHC) conducted a series of attic research projects from 1988to1997. Initially, there were few field test data to substantiate how attics dealt with air and moisture transfer. The CMHC research developed a test protocol for attic airtightness and air change testing and then proceeded to field testing of a variety of attics in different climatic areas. An attic model, ATTIX, was referenced against test hut data and used to simulate attic performance across Canada.

In this paper, design guidelines are presented for laboratory exhaust fans and stacks based on the contractor's installed experience in the field.

This paper discusses the development and application of standards of performance (SOPs) for HVAC&R equipment, plumbing systems, and building envelope systems in relation to maintaining acceptable indoor air quality (IAQ) in buildings. The utilization of the SOP procedure, developed in ASHRAE Research Project 853, will aid in the proper operation of systems and verify that acceptable building IAQ levels are obtained.

While monitoring the comparative performance of two test houses in Pittsburgh, Pennsylvania, it was noticed that the attic air temperature of one house with a plastic shake roof was consistently 20°F ( 11°C) cooler than its twin with asphalt shingles during peak summer cooling periods. More detailed monitoring of the temperatures on the plastic shake, the roof deck, and the attic showed this effect to be largely due to the plastic shake and not to better roof venting or other heat loss mechanisms.

This paper describes a residential research facility built for the experimental measurement of the relative energy and moisture performance of various residential building envelope components and systems. The building comprises 12 test bays on an east/west axis bounded on each end by a guard bay. The eastern six test bays are framed in steel, and the western six bays are framed in wood. Each half of the building contains a symmetrical mix of vented and unvented cathedral and attic roofing systems and is built above a heated basement.

One basic goal of the commissioning process is to make sure that the HVA C system is functioning as intended. In particular, it is intended that the HVAC system not only provide adequate ventilation for the building occupants but also achieve adequate pressurization of the occupied spaces to prevent the infiltration of unconditioned air. One technique for evaluating the performance of the HVAC system in these areas is to use continual, multipoint monitoring of carbon dioxide, carbon monoxide, and dew point at selected locations in the building and the HVAC system.

This paper presents results of a project initiated by ASHRAE and the National Research Council of Canada. The project applies both physical and numerical modeling to atrium smoke exhaust systems to investigate the effectiveness of such systems and to develop guidelines for their design. In this paper, results were obtained from a series of tests conducted using a large-scale physical model.

Residential air infiltration rates predicted by a detailed multizone computational model are compared with those predicted by a single-zone model. The multizone model is created using the public domain program CONTAM96, which allows the user to break the house into a number of Zones connected to one another and the outdoors by leakage paths with user-defined characteristics. Actual floor plans for a ranch-style house and typical published leakage characteristics of residential building components are used to construct a very detailed model with roughly 2,000 zones and 7,000 leakage paths.

The use of raised access flooring systems for office environments has become much more frequent in recent years. Power and data cables housed in the floor cavity can easily be accessed and modified to accommodate changes in the occupancy and use of the space. This cavity can also be used as a supply air plenum, which allows introduction of conditioned air through the floor.