الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
is research is to study the characteristics of jet issuing
from a circular cylinder in cross air stream at different angles of
injection relative to the direction of main stream. Also, the
study includes the effect of the injected flow to the main stream
velocity ratio.
The jet nozzle used is two dimensional of 0.85 mm width
and 60 mm length, machined on a hollow circular cylinder of
9.5 mm outer diameter and 7.5 mm inner diameter. The length
of the cylinder is 300 mm.
The cylinder was mounted across a wind tunnel test
section of 300 mm width, 300 mm height and 600 mm length.
The main stream velocity was varied between 8 m/s and 13.3
mis, which are equivalent to cylinder Reynolds number
between 4800 and 8000. The jet has fixed Reynolds number of
3830. The injection angles were 0°, 30°, 60° and 90° relative to
the main stream direction. The experiments were carried out at
three ratios of jet to main stream velocities 5.2, 7.0 and 8.7.
Measurements were carried out using single constant
temperature hot wire anemometer mounted on automatic
traverse mechanism. In order to avoid the cylinder wake
circulation zone, measurements started at a distance of 3.6
times the cylinder diameter which is equivalent to 40 times the
jet width. Three other measuring stations were examined at 60,
80 and 100 times the jet width.
The results showed that changing the jet angle has a great
effect on jet development. Also, the results indicatedinterference between the cylinder wake and the jet wake which
results in creating a wake larger than that of the cylinder alone,
this obstruction depends on the injection angle. The results also
showed that the jet trajectory depends on the injection angle and
the velocity ratio. As the velocity ratio increases, the jet decay
is slower and the trajectory is more displaced from the cylinder
centerline. from injection angle point of view, while increasing
the angle of injection, the jet decay is faster and the trajectory is
displaced more. All cases showed that moving downstream, the
location of maximum velocity is more displaced and the decay
is greater. Comparison with similar previous work shows good
agreement.
VII
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