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temperature setting at 55°C, pressure setting at 12cmH2O and tube heating at 15W
.......................................................................................................................... 135
Figure 5.30 Comparison of model outputs and experimental results of Airflow
temperature at HADT lump30 vs. setting of tube heating under heating element
temperature setting at 55°C, pressure setting at 12cmH2O and normal room
temperature ....................................................................................................... 136
Figure 5.31 Comparison of condensation in HADT ................................................... 137
Figure 5.32 temperature in grooves of the corrugated HADT may be lower .............. 141
Figure 5.33 Condensate in grooves............................................................................ 141
Figure 5.34 Experimental setup for evaporation rate comparison between steady flow
and breath-added situation ................................................................................. 143
Figure 5.35 Comparison of in-HADT condensation between steady state and breathadded
situation .................................................................................................. 144
Figure 6.1 Reverse flow under different combinations of breath load and CPAP pressure
setting ............................................................................................................... 147
Figure 6.2 Percentage of exhaled air in inhalation under different combinations of
breath load and CPAP pressure setting when using nasal mask .......................... 148
Figure 6.3 Comparison of exhaled air re-inhalation between nasal mask and full-face
mask when there is reverse flow influence ......................................................... 150
Figure 6.4 Explanation of comparison between steady flow convection rate and average
convection rate of fluctuating flow (not to scale) ............................................... 151
Figure 6.5 Comparison of total amount of air flowing through the system in a 6 seconds
breathe cycle time between steady flow, normal and deep breath added situations
.......................................................................................................................... 152
Figure 6.6 Comparison of evaporation rate averaged in a 6 seconds breathe cycle time
between steady flow, normal and deep breath added situations .......................... 153
Figure 6.7 Comparison of average airflow temperature in HADT between normal breath
and deep breath under different tube heating when pressure setting is 4cmH2O,
heating element is at 55°C, ambient temperature and relative humidity at 22°C and
50% .................................................................................................................. 154
Figure 6.8 Airflow velocity in HADT under CPAP pressure setting at 4cmH2O with
normal breath .................................................................................................... 155
Figure 6.9 Fluctuation of airflow specific humidity in the chamber and at different
locations in HADT under CPAP pressure setting at 4cmH2O, Heating element
45°C with normal breath without tube heating when ambient temperature is 22°C
and relative humidity is 50% (the pink horizontal line is the specific humidity of
steady flow for reference) .................................................................................. 155
Figure 6.10 Fluctuation of airflow temperature in chamber and at different locations in
HADT under CPAP pressure setting at 4cmH2O, Heating element 45°C with
normal breath without tube heating when ambient temperature is 22°C and relative
humidity is 50% ................................................................................................ 156
Figure 6.11 Airflow velocity in HADT under CPAP pressure setting at 4cmH2O with
deep breath ........................................................................................................ 157
Figure 6.12 Fluctuation of airflow temperature in the chamber and at different locations
in HADT under CPAP pressure setting at 4cmH2O, Heating element 45°C with
deep breath without tube heating when ambient temperature is 22°C and relative
humidity is 50% ................................................................................................ 157
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