6|
Szabó et al.
Period. Polytech. Civ. Eng.
completed bridge case at high turbulence.
The RMS of
lift coefficient showed 20 percent difference in this par-
ticular case. On the other hand, however, the convergence
of drag force coefficient and Strouhal-number could be
observed as a function of mesh size.
The results of the
k–
ε and DDES models at low turbulence intensity were in
reasonable agreement. Based on the results the
k–
ε model
appeared to be appropriate to model vortex shedding phe-
nomenon in case of the investigated specific unfavorable
cross-sections. It should be mentioned, however, that it
was not the case for the streamlined Humen Bridge deck
section according to the Authors' study. There could be
no
vortex shedding observed, the flow were stabilized.
The DDES model was successful only,
with results
of
c
y
' = 0.060 and
St = 0.095. The detailed study is not
addressed in this paper.
5 Measured wind characteristics
The monitoring system recorded wind velocities and direc-
tions as well. The wind velocity distribution within a two
months deck construction period can be seen in Fig. 13.
In can be seen that basically low wind speeds prevailed
during the construction.
In Fig. 14 the wind direction distribution can be seen.
Wind from the south-east was the most likely contrary to
the north-west direction prevailing in Hungary. The bridge
axis is nearly parallel with the north-south direction.
The bridge cantilever
was attacked under skew wind,
which was unfortunate in terms of validation of simulation.
Chia sẻ với bạn bè của bạn: 
