Paper 4
Influence of Induction Box Ports on Near Flow Field Mixing
M.I.
Khan
Scott
Wilson, Central Boulevard, Blythe Valley Park, Solihull, West Midlands B90
8AH
Abstract
This paper presents the
influence of air blown through an injection nozzle in a circular section
induction box on the axial jet and air induction. The effect of the
turbulent jet on the axial mean streamwise velocity decay, turbulence
characteristics, mass entrainment and
temperature distribution in the near flow field of an enclosed numerical
space is investigated. Convergence of the steady state simulations is
achieved by using the RNG kappa-epsilon turbulence model. Comparisons of
the axial mean streamwise velocity decay, turbulence
characteristics and the temperature distribution in an enclosed space are
reported for an injection nozzle, and another similar simulation was
conducted for a circular section induction diffuser box with open ports at
specific positions to evaluate its performance. The numerical
analysis was validated by prototype experiments using a similar injection
nozzle in a test room 11 m in length, 5.5 m wide and 2.5 m
high. Measurements of the streamwise velocity and temperature distribution
were made inside the room on a grid with the help of a hotwire
anemometer and digital thermometer, respectively. From the analysis
of the data, it was found that the near flow field streamwise velocity,
turbulence kinetic energy and air entrainment characteristics of the flow
were significantly influenced by the air induction diffuser ports.
Key words: primary
flow, secondary flow, turbulence, induction box, near flow field mixing.
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Contents
Paper
1
Editorial: Summer Comfort and Cooling - an INIVE Workshop
Paper
2
Space Planning, Ventilation and Energy Efficiency in Offices
Paper
3
Unveiling Energy Saving Techniques for Cooling in Residential Buildings in
Ghana
Paper
4
Influence of Induction Box Ports on Near Flow Field Mixing
Paper
5
Prediction of Flowfield and Acoustic Signature of a Split-type Air
Conditioner
Paper
6
The Use of Impulse Ventilation to
Control Pollution in
Underground Car Parks
Paper
7
Estimation of the Wind Speed in Urban Areas – Height less than 10 Metres
Paper
8
Utility of Wind Catchers for Nocturnal Ventilation
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