Typical Air-Conditioning Process

Typical Air-Conditioning processes are:

• Sensible Heating / Cooling

• Cooling and dehumidification

• Heating and humidification

• Adiabatic Humidification

• Adiabatic Mixing of Air

Governing equations:

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STATE is a point, and PROCESS (sequence of states) is a line on the Chart. Process may involve:

• Sensible Heat (change TDb, constant W)

• Latent Heat (constant TDb, change W)

• Both

2.3.1 Sensible heating and cooling

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Wx

Ti

H

Example

Determine the energy (heat flux) required for sensible heating of air at 15°C and 50% RH to 32°C. Also find fa.

Given: State 1: 15°C, RH=50%, State 2: 32°C Find: q, fa

Solution:

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Heat Flux:

Relative humidity:

From the psychrometric chart (the process is a horizontal line): Heat flux is Relative humidity:

How to check iffFis constant, i. e. no latent heat?

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