Physical
Concepts and
Basic
Fluid Mechanics
59
For real f(t), then c.,
is c,'s complex conjugate, and if phase
is
considered, then:
where
and
1
-b,
s,
=
tan-
(-)
an
(3.2.24)
(3.2.25)
In terms of pulsatile
blood
pressure waveforms p(t), we have for mean
pressure:
(3.2.26)
and for the nth harmonic of the pressure waveform:
For the corresponding flow waveform harmonic component, we have
(3.2.28)
Vascular impedance, expressed as the harmonic ratios
of
pressure to
flow, is:
2,
(0)
=
12,
(w)le'8"
(3.2.29)
From which, it
is
clear that the magnitude and phase for the
corresponding harmonics are
