Experimental and Numerical Study of Swirling ... - Solid Mechanics

Experimental and Numerical Study of Swirling Flow in Scavenging Process for 2-Stroke
Marine Diesel Engines
Chapter 4
values of vrv z . An overall picture of the distribution can be understood in
this way that at z1, the highest values of v v z are observed in the vortex
region whereas the vrv z are dominant in the near wall region. The region
in between has the minimum values for both the shear stress components.
With swirl decay along the flow, the spatial distribution of these shear
stresses increase and magnitude decreases.
4.2.7 Average Turbulent Kinetic Energy
The average turbulent kinetic energy (TKE) k is given by
1
k uu vv ww
(4.1)
2
From equation (4.1), the turbulent kinetic energy represents half the sum of
normal components of Reynolds stresses. Thus a possible bias, as discussed in
section 4.2.6, due to vortex core precession can also be expected in the values
of k in the vortex core region.
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Swirling Flow in a Pipe