Prediction of Air Distribution in a Ventilated Room

This article examines a solution procedure which can determine the flow in an air-conditioned room. The method is based on the solution of a group of equations for the flow (four non-linear partial differential equations) by means of a numerical method. Comparison with test results indicates that the method studied is suitable for prediction of air movement in an air-conditioned room when the flow is steady and two-dimensional. The method can be extended to give the required information for the evaluation of thermal comfort in the room.

Natural Venting to Control Smoke Movement in Buildings Via Vertical Shafts

Effects of vertical shaft venting on smoke movement in tall buildings are examined in order to obtain conditions for minimum smoke filtration into upper floors, stairways, and elevator shafts during fires. Results show that sufficient bottom venting will nearly eliminate flow of air into shafts, while top venting reduces flow from shafts. Either should reduce smoke transfer between levels. Multiple shaft buildings benefit from top ventingsome and bottom venting others, reducing necessary vent size for sufficient ventilation.

Prediction of the Anticipated Air Volume Passing Through Buildings by Means of the Air Current Analogue

For proper control of the ventilation in a building, it is necessary to know the factors involved. These include (1) the climate, including temperature, wind direction, and wind velocity, (2) the building performance, (the interconnections b

Use of Gas and Particle Tracers in the Study of Infection Transmission

One important factor in the spread of airborne infection must be the movement of the air itself i.e. the ventilation, although an exact correlation of it with the risk of infection has yet to be found. As part of an infection survey in a hospital ward we made a detailed study by physical methods of the movements of the air and of the transport of particles by this means. A description is given of the methods employed.

The Averaging Pressure Tubes Flowmeter for the Measurement of the Rate of Airflow in Ventilating Ducts and for the Balancing of Airflow Circuits in Ventilating Systems

This paper describes an original investigation of a new flowmeter and a method of balancing of airflow circuits in low pressure ventilating systems. The flowmeter is simple and robust in its construction, imposes virtually no resistance to

The Evaluation of Ventilation

The problem of describing quantitatively the effective ventilation in a room when the air within the room is imperfectly mixed is discussed. It is suggested that the protection afforded by the ventilation to any given position against air

Ventilation Theory and Practice

In this paper it is our intention to consider that ventilation is the circulation or passage of an air supply through an enclosure resulting in the displacement of some or all of the air contained in that enclosure by thesupply air. Depending on the character and condition of the supply air it can dilute or change the quality of the air in an enclosure as well as alter its temperature and humidity. A mathematical analysis of the ventilation process appears later in this paper.

The use of a building enclosure siding as a passive cooling device

The effect of ventilation in the space between a main wall and an exterior siding is examined with respect to reducing the building's cooling load. The buoyant force of the air in the space is considered as the motive force of air flow and the effect is treated as a problem of simultaneous heat and mass-transfer. A simulation program of heat and air flows in a wall has been developed using laminar flow theory, and its validity is examined by thecomparison of the simulation results with a weather exposed full-scale model test.

The Study of Air Flow, Ventilation and Air Movement in Small Rooms as Effected by Open Fireplaces and Ventilation Ducts

This paper describes part of a research on the influence of environment on physiological reactions and thermal comfort. Experimental rooms and apparatus are described and the imperfections in some of the instrumental methods - especially in respect to the measurement of air change by tracer substances - are noted. A brief description of a method to measure air change is givenin which CO2 is used. The importance of limiting the rate of air change in rooms heated by fires - as a means to save heat - is stressed.

The ventilation of deep-plan buildings using lightwells and courtyards

The use of lightwells and courtyards for natural ventilation in high-rise buildings is exaimed using both wind tunnel and field measurements of the pressures and neutral pressure zone caused by wind and temperature differences. Though air flow patterns are complex for complex building designs, air exchange rates in lightwells and courtyards were generally seen great enough to assure clean air for natural ventilation via air infiltration. However the cost of land in urban settings will probably make mechanical ventilation systems the economic choice.

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