AirCon Flashcards
1
Q
Indoor spaces are subjected to…
A
Heat gain & losses
2
Q
How to maintain a desired indoor condition?
A
- heat energy transfer either from space or to space
- to compensate for heat gains & losses
3
Q
How can thermal comfort be defined?
A
The condition of mind that expresses satisfaction with thermal environments.
4
Q
How is thermal comfort judged?
A
- temperature sensation from skin
- moisture sensation from skin
- deep body temperature
- efforts required to regulate body temperature
5
Q
How are heat exchanged with the environment?
A
- Convection
- Evaporation
- Radiation
6
Q
Percentage of Convection
A
30%
7
Q
Percentage of evaporation
A
25%
8
Q
Percentage of radiation
A
45%
9
Q
Factors affecting thermal comfort
A
- air temperature
- relative humidity
- air velocity
- mean radiant temperature
10
Q
General temperature of Air Temperature
A
- 23°C to 28 °C
- green mark office: ± 24°C
11
Q
What happens when air temperature increase?
A
Evaporation rate ↑
Convection ↓
12
Q
General range for relative humidity
A
30% to 70%
13
Q
What happens when relative humidity increase
A
Evaporation rate ↓
14
Q
General speed for air velocity
A
0.2 m/s
15
Q
What happens when air velocity increase?
A
Evaporation rate ↑
Convection rate ↑
