J056021 乱流境界層中に点源供給された濃度場の乱流特性([J05602]乱流における運動量,熱,物質の輸送現象(2))

Abstract

An experimental investigation has been made on the concentration field dispersed from a ground-level point source in a turbulent boundary layer. Fluctuating concentration signals of ethylene are measured by a fast-response flame ionization detector (FID). The mean concentration profiles are well described by the Gaussian plume model with a modification of the exponent in the wall-normal direction. The cross-sectional distributions of the concentration fluctuation intensity show two maxima near the wall. It is found that the instantaneous concentration field spreads very widely compared with the mean field.