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Appendix III. Regression of the air temperature increase after
flowing through the blower
This appendix is to explain the data process of obtaining the relationship between
enthalpy increase and CPAP pressure setting and the corresponding data process.
Repeating the tests under three different ambient conditions as listed below:
Temperature 10°C and relative humidity 50% for cold and dry condition
Temperature 20°C and relative humidity 70% for most common room condition
Temperature 35°C and relative humidity 90% for hot and humid condition
The thermal enthalpy increase is calculated by Eq. (3.2). When under temperature 10°C
and relative humidity 50%, the specific humidity level is d = 0.003761 (kg/kg) and the
result is shown below:
Table III. 1 Airflow temperature and enthalpy increases after flowing through ADU when ambient
temperature is 10°C and relative humidity is 50%
P-set(cmH2O) T ( C)
Ao
- 184 -
T ( C)
Ao
H
( J / kg)
4 12.29 2.29 2311.15
6 13.12 3.12 3141.45
8 13.87 3.87 3905.57
10 14.56 4.56 4601.74
12 15.29 5.29 5332.23
14 15.95 5.95 6000.24
16 16.47 6.47 6525.47
18 16.63 6.63 6680.55
20 17.10 7.10 7160.88
When under temperature 20°C and relative humidity 70%, the specific humidity level is
d = 0.0101 (kg/kg) and the result is shown below: