The ventilation rate and energy consumption of one of the ECRC test houses was monitored continuously during one heating season, with one bedroom window open by various amounts. Results show that a very small window opening is sufficient to satisfy ventilation requirements most of the time.
This work deals with different aspects of air movements in building components. The investigation shows to what degree the concept of fluid mechanics can be applied to problems concerning air flows in building componenets. The applicable parts of fluid mechanics are presented as thoroughly as possible. Based on this concept, routines are outlined to make it possible to handle complex flow and pressure distribution problems. Both manual and computer calculation routines are described and the way they can be used is demonstrated in a number of examples.
Describes a computer technique for analysing air movement resulting from stack effect in a tall building. Describes the method which determines the air flows for all possible paths through exterior walls and within the building. The building is divided into multi-storey zones based on the design of the building and the HVAC system. Gives an example of the method applied to a building under two different climatic conditions. Considers the problem of thedifficulty in opening doors due to excess pressure across the door.
Reports experiments using sulphur hexafluoride as a tracer gas to obtain quantitative data on actual residence time distributions in rooms and hallways and contamination caused by reentry of laboratory fume hood exhausts into a building. Defines a factor k which gives a measure of the mixing of fresh withstale air in part of a room. Measured values of k varied from 0.3 to 0.7 insmall rooms without fans. Discusses two experiments to find the amount of exhaust fumes reentering the ventilation system of a building.
Presents diagrams showing the behaviour of air currents in two passive solar houses. Suggests some straightforward means by which repetitive patterns of discrete currents can be engineered. An appendix briefly outlines the operation of a discrete current flat plate collector with a 65 - 75% normal winter efficiency.
Gives theoretical calculation of the amount of air which moves from one room to another due to a temperature difference between the two rooms. Suggests the possibility of reducing the heating or cooling load by allowing an overpressure in one of the two rooms.
Describes in detail a multi-cell model for predicting ventilating airflows. Gives equations for flow through cracks, wind and stack effect. States that comparisons between prediction and measurements indicate that the method is capable of giving relatively high accuracy for a wide range of ventilation conditions. Discusses advantages and disadvantages of multi-cell and single-cell methods. Argues that multi-cell approach is potentially more accurate and more useful.
Treats importance of keeping uncontrolled ventilation to a minimum in buildings equipped with balanced ventilation. Provides theoretical and experimental description of leakage of air past windows. Includes comparison between standards of different countries. Discusses effect on building ventilation of variations of wind and outdoor temperature. Considers in conclusion measurement of air flows between rooms in a building. Describes development of tracer gas method based on computer-assisted evaluation.
Describes instrumentation used to measure air flow and pressure. Presents laws for turbulent and laminar flow in a wind tunnel. Reports model experiments to investigate the flow behind a solid screen and control experiments to check the model laws. Discusses measurements made at full scale on a school and on a model of the school. Describes experiments on the shelter behind houses and the dispersal of smoke from a chimney.
Describes computer program developed by BSRIA to predict ventilation rates and directions of air flow in buildings for given sets of conditions. These conditions are wind speed and direction, temperature differences between inside and outside the building, air leakage characteristics of the components and the mechanically induced air flow rates. The report is in the form of anoperating manual for the program.
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