IMT Analytics SmartLung 2000, User Manual, Page: 18 / 44

Page 18
English
Approvals
The test lungs meet CE guidelines.
Resistance curves
Due to the non-laminar flow, the resistance Rp (flow
resistance, parabolic resistance) depends on the flow.
As the the flow rate increases, the resistance increases
linearly and the pressure increases as the square of the
flow rate. It therefore behaves similarly to the resistance
of an endotracheal tube.
Pressure drop P = K × flow
2
Resistance R = K × flow
With K defined for each Rp:
Rp5 Rp20 Rp50 Rp200
K 2.7 17.61 108.7 2440
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
0 20 40 60 80 100 120 140
)ra
b
m(
P p
or
D e
rus
ser
P
Flow (L/min)
Rp50
Rp200 Rp20
Rp5
The pressure drop P for various Rp values at different flow rates
(parabolic curve)