Flute acoustics: measurement, modelling and design - School of ...

4.3. RESULTS AND DISCUSSION 63
0.9
this work
Dalmont et al. 2001
0.8
0.7
cyl
/ a
0.6
0.5
0.4
0.3
0 0.2 0.4 0.6 0.8 1
flange ratio
Figure 4.7: The measured length correction δ cyl for radiation from open finger holes of length
5.0 mm compared to the fit-formula of Dalmont et al. (2001). The ‘flange ratio’ is the ratio of
the radius of the finger hole to the radius of the cylindrical flange.
10 6 frequency (Hz)
b/a = 1.0
10 5
Z a
(Pa s m 3 )
10 4
b/a = 0.5
10 3
500 1000 1500 2000 2500 3000 3500
Figure 4.8: The series impedance Z a for open holes of length 2.5 mm.