LoginA set of diagrams for estimating flow coefficients and exponents in the power law flow equation for cracks are presented.
12th AIVC Conference - Ottawa, Canada - 24-27 September 1991
The 12th AIVC Conference - Air movement and ventilation control within buildings, was held in Ottawa, Canada, 24-27 September 1991.
Contains 88 papers.
Volume content
Modelling of airflows, temperatures and contaminant levels for localized ventilation systems. | 1991 | English
Results of 3-D computational fluid dynamic simulations of the air flows, temperature distribution and contaminant remove efficiencies for typical workstation configurations which include the option for localized supply of outdoor air will be prese
Experimental investigation of convective couplings across various doorways under horizontal temperature gradients. | 1991 | English
Inter-zone convection affects the general movements of air in a building and must be evaluated for accurate thermal zones heat and mass balance.
A new approach for the numerical identification of interzonal airflows from tracer gas measurements. | 1991 | English
This paper presents a new approach to determine the interzonal airflows of a multizone system using tracer gas measurements.
Both infiltration and exfiltration has a predominant influence on the space heating requirements in cold climates. Good predictive design methods are required to estimate the air leakage component in buildings.
A mathematical model has been developed which will facilitate the prediction of infiltration rates within multi-zone buildings.
Integrated forced-air heating and ventilation systems: evaluation and design considerations. | 1991 | English
Mechanical systems which use common ducts for combined heating and ventilating functions are becoming popular in the Pacific Northwest (U.S.).
Definition of the flow parameters at the room inlet device - measurements and calculations. | 1991 | English
Due to the limitations of computer storage and time the flow boundary conditions at an air inlet device have to be specified for numerical simulations of air flow patterns in rooms.
The evaluation of a code can be done by investigating two items: solving the correct equations and solving equations correctly and eficiently. An indoor airflow code VentAirI has been developed and is evaluated here.
Theoretical and experimental analysis of different ventilation strategies in a test room. | 1991 | English
The paper presents an original computer code for the analysis of contaminant diffusion in rooms developed at the Politecnico di Torino and its experimental validation by means of a test facility located at the University of Basilicata (Potenza).
A new passive tracer gas method for ventilation measurements is described. The method utilizes passive tracer gas release from aliquid perfluorocarbon compound contained in a glass vial, equipped with a teflon membrane.
The passive perfluorocarbon method (PFT-method) has been successfully applied in ventilation measurements in rooms. The method is, in principle, also applicable to air flow measurements in ventilation ducts.
The knowledge of IEA-Annex 14 'Condensation and Energy' has been applied to develop a new strategy for humidity control in dwellings. The presented control element assures safe prevention from mould growth at a minimum energy consumption.
Field investigations were undertaken on five houses to determine the potential for improved performance and lower costs through the use of a demand controlled ventilation (DCV) systems.
The study recommends adoption of the new higher ventilation rates, but with the use of alternative occupancy densities.
The use of test chambers for characterising the emissions of volatile organic compounds from indoor building materials. | 1991 | English
Increasing interest is attributed to the problem of the accumulation of organic vapours emitted from indoor building materials due to an effective insulation of buildings with low ventilation rates.
Measurement of the entrance length and friction factor of ducts using tracer gas techniques. | 1991 | English
We describe the use of constant injection and pulse injection techniques for measurement of airflow in a duct. Tracer-gas measurements were compared with measurements made using a pitot tube and a hot-wire anemometer.
The possibility of unacceptable internal air pollution levels can cause concern at the design stage given the potential for cross contamination between building exhausts and ventilation intakes is there.
The present work is an investigation of ground heat exchangers for the air-conditioning of the supply air to residential buildings.
Performance analysis of demand controlled ventilation system using relative humidity as sensing element. | 1991 | English
This paper evaluates the suitability of humidity-controlled house ventilation system to determine (i) the effectiveness of relative humidity as a sensing element, and (ii) the operating and performance characteristics of such ventilation strategy.