We need air
We need ventilation in buildings and it must satisfy several different criteria.
It must be reliable, flexible and well-functioning, adaptable, and responsive to different needs and unusual events.
Ventilation needs to be provided for both people and buildings.
Do you know?
Do you know that natural ventilation is historically the most widely used ventiation in residential and other types of buildings?
Today, buildings have modern windows that are airtight and efficient, so natural ventilation (via infiltration) is limited to only small amounts of air exchange and natural ventilation (via airing/windows opening) often takes too much effort for building occupants.
Therefore, today it is difficult to keep ventilation requirements using just natural ventilation.
Fundamentals of mechanical ventilation
Mechanical ventilation is one of the systems that keeps a habitable environment.
Purpose of mechanical ventilation:
- To heat or cool the incoming air
- To circulate/move the air in a room
- To supply/exhaust the required air amount in the room
Basic information about mechanical ventilation:
- Ventilation is operable independent on exterior conditions
- Requires precise operation control
- Provides temperature and humidity (and other sources) control
Mechanical ventilation is based on pressure difference and caused by dynamic pressure of a mechanical device - fan/blower.
Ventilation consists of 3 main parts:
- Ventilation rate – the amount and quality of the outdoor air
- Airflow direction – the flow of air within a building, from “clean” to “dirty” areas
- Air distribution – the delivery of outside air and removal of pollutants
Basic principles of mechanical ventilation:
- Overpressure ventilation
- Balanced ventilation
- Underpressure ventilation
Mechanical ventilation consists of several parts, i.e. air handling unit (AHU), ducts, air supply/exhaust devices, dampers, fan coils, heating/cooling unit, etc.