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Abstract
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Totally, spur dike is an economical way to preserve
morphology of rivers. Numerical methods can be useful
for evaluating hydraulic parameters for spur dike because
of their reduced simulation time, while experimental ones
take a long time and need lots of tools to simulate any models.
In this paper, flow patterns around a T-shape spur dike
and a support structure, which is located upstream of the Tshape
spur dike, is analyzed in 90◦ bend channel by Flow-3D
model. The numerical and laboratory data are compared in
longitudinal section to verify numerical model. The results
show very good correspondence between numerical and laboratory
data. After verification numerical model, a support
structure has been installed upstream of the T-shape spur dike
with 3, 5, 7 and 9 times distance longer than the length of the
T-shape spur dike. The support structure altered flowpatterns
and hydraulic parameters such as power of secondary flow
and separation zone in all of sections. By increasing support
structure distance from 3L up to 9L, the power of secondary
flow around main spur dike decreases by 40–120% and the
length of separation zone increases from 0.8 to 2.5 times
bigger than the length of T-shape spur dike.
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