Abstract: Channel junctions can be analyzed in two ways of
division (lateral intake) and combined flows (confluence). The
present paper investigates 3D flow pattern at lateral intake using
Navier-Stokes equation and κ -ε (RNG) turbulent model. The
equations are solved by Finite-Volume Method (FVM) and results
are compared with the experimental data of (Barkdoll, B.D., 1997)
to test the validity of the findings. Comparison of the results with
the experimental data indicated a close proximity between the two
sets of data which suggest a very close simulation. Results further
indicated an inverse relation between the effects of discharge ratio
( r Q ) on the length and width of the separation zone. In other words,
as the discharge ration increases, the length and width of separation
zone decreases.
Abstract: Generally flow behavior in centrifugal fan is observed
to be in a state of instability with flow separation zones on suction
surface as well as near the front shroud. Overall performance of the
diffusion process in a centrifugal fan could be enhanced by
judiciously introducing the boundary layer suction slots. With easy
accessibility of CFD as an analytical tool, an extensive numerical
whole field analysis of the effect of boundary layer suction slots in
discrete regions of suspected separation points is possible. This paper
attempts to explore the effect of boundary layer suction slots
corresponding to various geometrical locations on the impeller with
converging configurations for the slots. The analysis shows that the
converging suction slots located on the impeller blade about 25%
from the trailing edge, significantly improves the static pressure
recovery across the fan. Also it is found that Slots provided at a
radial distance of about 12% from the leading and trailing edges
marginally improve the static pressure recovery across the fan.
Abstract: This paper analytically investigates the 3D flow
pattern at the confluences of two rectangular channels having 900
angles using Navier-Stokes equations based on Reynolds Stress
Turbulence Model (RSM). The equations are solved by the Finite-
Volume Method (FVM) and the flow is analyzed in terms of steadystate
(single-phased) conditions. The Shumate experimental findings
were used to test the validity of data. Comparison of the simulation
model with the experimental ones indicated a close proximity
between the flow patterns of the two sets. Effects of the discharge
ratio on separation zone dimensions created in the main-channel
downstream of the confluence indicated an inverse relation, where a
decrease in discharge ratio, will entail an increase in the length and
width of the separation zone. The study also found the model as a
powerful analytical tool in the feasibility study of hydraulic
engineering projects.