Summary: | 碩士 === 國立中央大學 === 土木工程學系 === 86 === Smoke released from a stack in the vicinity a rectangular
building wereinvestigated in a towing tank. Trajectories and
concentration distributionsof smoke were measured by the planar
laser-induced fluorescence (PLIF)and image processing method.
This method allows us to investigate thetemporal-spatial
distribution of the smoke, which is much more difficult toobtain
from traditional point tracer measurements. The relative height
ofstack Hs/Hb, location L/Hb, velocity ratio Ur and smoke
densimetricFroude no. Fo were systematically varied in the
experiment. It was found,downwash will happen behind the
building when Ur < 2.4. Thisphenomenon has a marked effect on
the smoke trajectory and its near-fielddilution. The results of
this study can be used for the design of smoke stack.
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