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  2. Air changes per hour - Wikipedia

    en.wikipedia.org/wiki/Air_changes_per_hour

    Air changes per hour, abbreviated ACPH or ACH, or air change rate is the number of times that the total air volume in a room or space is completely removed and replaced in an hour. If the air in the space is either uniform or perfectly mixed, air changes per hour is a measure of how many times the air within a defined space is replaced each hour.

  3. Building performance simulation - Wikipedia

    en.wikipedia.org/wiki/Building_performance...

    A simulation model is an abstraction of the real building which allows to consider the influences on high level of detail and to analyze key performance indicators without cost-intensive measurements. BPS is a technology of considerable potential that provides the ability to quantify and compare the relative cost and performance attributes of a ...

  4. Coefficient of performance - Wikipedia

    en.wikipedia.org/wiki/Coefficient_of_performance

    The heat pump itself can be improved by increasing the size of the internal heat exchangers, which in turn increases the efficiency (and the cost) relative to the power of the compressor, and also by reducing the system's internal temperature gap over the compressor. Obviously, this latter measure makes some heat pumps unsuitable to produce ...

  5. Constant air volume - Wikipedia

    en.wikipedia.org/wiki/Constant_air_volume

    Constant air volume (CAV) is a type of heating, ventilating, and air-conditioning system.In a simple CAV system, the supply air flow rate is constant, but the supply air temperature is varied to meet the thermal loads of a space.

  6. Building airtightness - Wikipedia

    en.wikipedia.org/wiki/Building_airtightness

    An airtight building has several positive impacts [3] when combined with an appropriate ventilation system (whether natural, mechanical, or hybrid): [4] Lower heating bills due to less heat loss, with potentially smaller requirements for heating and cooling equipment capacities; Better performing ventilation system

  7. Stack effect - Wikipedia

    en.wikipedia.org/wiki/Stack_effect

    The result is either a positive or negative buoyancy force. The greater the thermal difference and the height of the structure, the greater the buoyancy force, and thus the stack effect. The stack effect can be useful to drive natural ventilation in certain climates, but in other circumstances may be a cause of unwanted air infiltration or fire ...

  8. Negative room pressure - Wikipedia

    en.wikipedia.org/wiki/Negative_room_pressure

    Schematic of a network of rooms where air (shown in blue) flows in one direction from the corridor into the negative pressure room (green). Exhaust air is safely removed from the area through a ventilation system. Negative pressure is generated and maintained in a room by a ventilation system that continually attempts to move air out of the ...

  9. Specific fan power - Wikipedia

    en.wikipedia.org/wiki/Specific_fan_power

    In the case of an ideal lossless fan system (i.e. =) the SFP is exactly equal to the fan pressure rise (i.e. total pressure loss in the ventilation system). In reality the fan system efficiency is often in the range 0 to 60% (i.e. η t o t < 0.6 {\displaystyle \eta _{tot}<0.6} ); it is lowest for small fans or inefficient operating points (e.g ...