Load Calculation Of Psychrometry

Summer air conditioning aims to keep indoor spaces cool and comfortable during hot and humid weather.
The main psychrometric process used is cooling and dehumidification.
In this process, warm and humid air from the room is drawn into the air conditioning unit.
The air passes over a cooling coil that is colder than the dew point temperature of the air.
As a result, the air temperature drops and moisture condenses out, reducing humidity.
The cooled and dehumidified air is then supplied back into the room to maintain desired conditions.
This improves comfort by lowering both temperature and humidity.
This process is essential for comfort cooling in homes, offices, and commercial buildings during summer.

Chemical dehumidification is a method of removing moisture from air using chemical substances called desiccants.
In this process, moist air passes over or through materials like silica gel, activated alumina, or calcium chloride.
These chemicals absorb or adsorb the water vapor from the air due to their high affinity for moisture.
This reduces the humidity level in the air and makes it suitable for applications that require dry air.
Chemical dehumidifiers are commonly used in industries, storage areas, and air conditioning systems where precise humidity control is needed.
Unlike cooling-based dehumidification, chemical dehumidification does not rely on refrigeration cycles.

Winter air conditioning focuses on providing comfortable indoor conditions during cold weather.
In winter, the air outside is usually cold and dry.
When this cold air enters a building, it often needs to be heated to a comfortable temperature.
However, heating alone can make the air even drier, causing discomfort like dry skin and irritation.
To maintain comfortable humidity levels, humidification is added along with heating.
This combination keeps the temperature warm and moisture at a pleasant level.
Cooling and dehumidification are summer processes.
Sensible cooling reduces temperature but is not needed in winter.
Therefore, heating and humidification is the correct answer for winter air conditioning.

Dehumidification is the process of removing moisture from the air to reduce humidity levels.
Chemicals like calcium chloride, silica gel, and activated alumina are known as desiccants.
They absorb moisture from the air and are widely used in dehumidifiers.
This helps keep indoor air dry and prevents mold, corrosion, and moisture damage.
Humidification is the opposite — adding moisture.
Sensible cooling and heating change air temperature but do not directly remove or add moisture using chemicals.
Therefore, these chemicals are used for dehumidification.

Dehumidification is the process of removing moisture from the air while keeping its dry bulb temperature unchanged.
This process reduces the air’s humidity level, making the environment more comfortable, especially in humid climates.
Dehumidifiers or air conditioners perform this by condensing water vapor onto a cold surface.
Humidification is the opposite — it adds moisture to the air.
Sensible cooling lowers air temperature without changing its moisture content.
Sensible heating raises temperature without changing humidity.
Therefore, removal of moisture alone is correctly called dehumidification.

When air is heated and its temperature increases without any change in its moisture content, it is called sensible heating.
In sensible heating, only the dry bulb temperature of the air rises, but the specific humidity (amount of water vapor per kg of dry air) remains constant.
This process occurs in applications like heating systems and air conditioning during winter.
Humidification adds moisture to the air.
Sensible cooling removes heat without changing humidity but in the opposite direction — cooling instead of heating.
Dehumidification reduces the moisture content.
Therefore, heating air without changing its specific humidity is correctly called sensible heating.