Paper 2: Volume 4 No.4 March 2006 Edition
Determination of Air Outlet C-Values by Means of
Interferometry
E.
Janotkova and M. Pavelek
Department
of Thermomechanics and Environmental Engineering
Brno
University
of Technology, Technicka 2, 61669
Brno
,
Czech Republic
Abstract
The
basis for room air distribution solutions in ventilating and air
conditioning rooms is the calculation of velocities in air jets from
supply outlets. To calculate velocities, the C-value of the air outlets
must be known. The aim of this contribution is to acquaint readers with a
non-traditional method for defining the C-value of an outlet from the
angle of air jet expansion in the main jet zone, determined using
interferometric visualization of the jet. The principles of
interferometric measurements in transparent environments are demonstrated,
along with their evaluation via special software developed for evaluating
recorded interferograms. The C-value of slot and rectangular outlets is
determined using the method introduced here. Results demonstrate the high
precision of the method, and that the C-values of outlets can be defined
effectively from the visualization records.
Key
words: air
jets, velocity, supply air outlets, C-values, interferometry.
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Sapporo 2003. |
