Summary: | 碩士 === 逢甲大學 === 材料與製造工程所 === 96 === The objective of this research is to investigate the flow interference
phenomenon of a circular cylinder near a plane boundary, arranged
side-by side in cross flow with various pitch ratios at Reynolds number of
1000. The analysis was performed by using the FLUENT software, The
flow forces acting on the main cylinder, flow characteristics, and Strouhal
numbers are investigated for different gap-ratios of the cylinders.
Learnt by the analysis result, when the interval G/D is 3.5, cylinder
and plate have not interfered with the phenomenon and taken place each
other, the in other words single cylinder, with putting in freedom flows in
a plate. When G/D reduces, postpone and then the trend that move ahead
of time first in some positions of separation of layer of dull and
stereotyped border. At G/D≧1.8, the vortex shedding frequency of
cylinder does not change; At 1.2≦G/D<1.8, the increase of vortex
shedding frequency dwindling of the intervalin; At G/D =1.2 reach all
interval of maximums vortex shedding frequency. At G/D<1.2 vortex
shedding frequency reduce and appear, lower trend with interval.
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