OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
5. The duct/diffuser effectiveness (as defined C p / C p (ideal) ) was found 68% for duct with 600 mm C L & 764 mm
R C while the duct/diffuser effectiveness (as defined C p / C p (ideal) ) was found 50.7% for duct of 300 mm C L &
382 mm R C .
6. At the merger, two streams are mixed with each other, centrally core flow with almost uniform intensity of
pair of vortices found. The secondary flow pattern seen at the exit plane shows presence of two pair of
vortices with central pair having weak intensity. When two streams mixed at the merger plane distortion
occurs in the flows and it is finally settle down at the exit and flow distribution is uniform at the exit.
Notations
AR: area ratio (Outlet area of the duct / Inlet area of both limbs of
the duct)
C P: coeff.of static pressure recovery (=(Ps o - Ps i )/P dyn(in) )
U ave(in) :mass-averaged velocity at inlet,
(m/sec)
CV: convex surface
C Loss: coeff. of total pressure loss (=(Po i - Po o ) / P dyn(in) ) P wall: wall static pressure, (N/m 2 )
Ps i: mass-averaged static pressure at inlet, (N/m 2 )
Ps o: mass-averaged static pressure at outlet, (N/m 2 )
CC: concave surface
L: axial length along duct, (m)
Po i: mass-averaged total pressure at inlet, (N/m 2 ) ρ : fluid density, (kg/m 3 )
Po o : mass-averaged total pressure at outlet, (N/m 2 )
P dyn(in) : dynamic pressure at inlet (=1/2 ρU 2 ave(in) ), (N/m 2 )
h: height of duct at inlet,(mm)
w: width of duct at inlet,(mm)
X: distance along the centerline of the duct from the inlet plane, (m) C L : centerline length (mm)
Y: distance perpendicular to the centerline of the duct from the inlet
plane, (m)
θ : rotation angle (angle of rotation of the five-hole probe), (deg)
U long :velocity in the axial direction,
(m/sec)
R C : radius of curvature (mm).
C p (ideal) = [1-{1/ (AR) 2 }]
Acknowledgement
The author is very grateful to Professor V. Seshadri & Professor S. N. Singh, Applied Mechanics Department,
IIT Delhi, for their support & help during the period of experimentation and many useful discussions. I am also
very grateful of staff members of different labs for their commitment and support, as provided during the tenure.
References
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