Stratification and Destartication
Stratification:
Strata mean layers, thermal strata refer to layers of different temperatures and thermal stratification refers to the process. Let us consider an example of a lake, at the bottom of the lake, the temperature of the water is very less compared to the top water layer. So there is the temperature difference between the bottom layer and top layer water.
Image 1: Stratification in the lake
Similarly, in the case of buildings, every building has open space. Depending upon the weather condition, the temperature in open space varies. In summer, as hot areas rise in open spaces, these hot air generated spread out across the area and makes the area denser. Also, the ceiling height matters the condition of the temperature in open space (when the ceiling height is more, cooler is the temperature at floor level).
Destratification:
Heat destratification results in thermal comfort. We can feel when we are thermally comfortable in the environment. Destratification is the act of controlling and changing the natural process of thermal stratification. Destratification also includes controlling heating, ventilation and air conditioning in an open area. Let us consider an example for a topmost floor of a building. To get thermal comfort, the ceiling is insulated by using insulation ( spray paint insulation on a terrace, foam insulation, etc.). To get better thermal comfort, Destratification fans like HVLS fans and axial fans can help de-stratify the air and help with heating and cooling.
Destratification fans:
Destratification fans are nothing but large ceiling fans that provide the most effective way to control and condition the air. This fan helps to circulate air in a proper way to control air in a very large open area. When the fan is used at proper speed and direction, it will push trapped heated air at the ceiling back down to floor level, reducing the temperature differences in the room.
Image 2: Epoch HVLS fans
Types of Destratification fans:
There are two types of fans used for destratification:
Preventative High Volume Low-Speed Blade or Propeller Fans: Just as the name implies, these fans prevent destratification before it happens by operating continuously along with the heating system. With large impeller blades or paddles, and slower motor speeds, this type of fan requires less energy compared to standard speed fans.
High-Velocity Axial Fans: Reactive fans operate at much higher speeds with airflows relative to the area they treat by pushing the air down to the floor level. Generally, with the temperature set, they can change the temperature difference. Once the temperature reaches the preset level, it shuts off.
What are the benefits of destratification fans?
A destratification ceiling fan not only makes the area comfortable but also helps during winter to distribute the heat evenly. During winter, such fans force the air to move in from the ceiling to the floor. Shop areas consist of heavy machinery and employees, HVLS fans can help not only distribute the warm air but also help to keep employees from overheating.
Following are the benefits of a Destratification fan:
- Reduction of Energy Costs: Destratification fans are highly energy-efficient, reducing the energy costs by 30% to 40%.
- Reduction of Pollutants for Cleaner Indoor Air: Nowadays, everyone is thinking ‘green’ – go green and save energy and the environment. Building managers and owners realize that green code compliance is essential. Stale, stagnant air is full of pollutants that can affect not only their products but their employees as well. Destratification fans can help with air circulation and minimize the risk of sick building syndrome (SBS). Sick building syndrome is often caused by stagnant, polluted air from chemical fumes, volatile organic compounds, pollen, and bio-aerosols. Sick building syndrome typically causes headaches, dizziness, and nausea while inside the building and resolves once outside the building. Using a destratification HVLS fan reduces pollutants from sitting at the floor area and increases ventilation, providing better air quality for employees and customers.
- Elimination of Condensation: Destratification fans help reduce condensation by circulating warm, humid air that is trapped in the ceiling and pushes it towards the warmer ground.
- Very low maintenance cost: The maintenance cost of a destratification fan such as Epoch HVLS fan is very less
What parameters to be considered while selecting destratification fans?
As we know there are different types of fans available in the market, so it can become confusing while choosing the best suitable fan for our needs. The two important things to consider while selecting a fan are area coverage and airflow of the fan.
The following are the additional important parameters which should be considered during the selection of a fan:
- Mounting and ceiling height to minimize air pockets or drafts;
- Number of fans required for a particular area;
- Installation position for optimal air distribution;
- Easy maintenance access;
- Noise levels;
- The direction of airflow.