Commercial buildings require mechanical ventilating systems, the specifications for which are included in the building codes. These codes specify the amount of outdoor air to be supplied per person for designed occupancy conditions. Many buildings such as retail establishments operate much of the time at occupancy loads well below the design. Thus, they are generally over ventilated and waste energy when operated according to the codes. A control system based on measurement of the carbon dioxide generated by the occupants was tested in a small bank in Pasco, Washington.
A large number of multifamily buildings have mechanical exhaust air ventilation. The control of such systems' function is often inadequate and adjustment is rarely carried out. One reason for this is the lack of simple methods for determining system performance and air change rates. The report describes a simple method and simple equipment for determining performance in terms of an installation's capacity curve or 'fan installation' curve. Defines terminology and measurement principle. Illustrates equipment and arrangement for measurements.
Describes the network procedure for calculating the most energy-conserving and economical form of natural ventilation of a building. Provides application examples in the form of the determination of mass air flows through doors and windows and cracks in industrial work sheds. Provides the results of a calculation of crack ventilation in winter with mechanical ventilation with positive pressure, plus optimisation of air flow through a cooling bed for hot rolled steel sections.
A computational procedure to predict expected rates of natural ventilation for buildings at the design stage is investigated. This procedure integrates three computational methods, namely one to predict temperature induced pressures, another to compute wind generated pressure distributions around buildings, and the third to analyse the networks of resulting air flows in buildings. Experiments show that these methods are valid. The three methods can be used not only for the prediction of natural ventilation, but also for many other environmental engineering applications, e.g.
Notes increasing complaints in Germany with the use of air conditioning and mechanical ventilation systems, despite them creating an indoor climate meeting the stipulations of German standard DIN 1946. The complaints are mainly of draughts, dry air, stale air and variable temperatures. Attributes most causes of complaint to the systems of air supply. Examines the drawbacks of various types of air supply system - dilution ventilation, window ventilation, displacement ventilation.
Effectiveness of ventilation as a major means of controlling indoor air quality was evaluated by correlating concentrations of gaseous (CO and CO2) and particulate (total) pollutants with two ventilation parameters. Pollutants are differently af
This paper presents a method for a more accurate calculation of air exchange in the mechanical ventilation of industrial halls with uniformly distributed heat load. The method has been developed on the basis of finding the relation between the
Resulting from experiences of a project by the German National Energy Research Foundation (NEFF), and further investigations, a recommendation is presented on the permeability of building envelopes in residential buildings, according to on hand ventilation devices. To find out the permeability, the air leakage at 50 Pa is evaluated. This can be found out with the differentiated pressure reading of the building.
Air management in residential or tertiary usage buildings constitutes one of the key points of energy control in buildings. The principle themes concerning air management are heating or air conditioning, and ventilation and air renewal, mechani
Due to the fact that loss of heat due to transmission is on the decrease, the loss of heat due to ventilation is becoming more important. Heat recovery units must be put into use to decrease the heat loss due to ventilation. If mechanical ventilation systems are used to create a minimum air change rate, air-tight windows are necessary - but if no ventilation grilles are used they are out of place.
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