Turbulent structure in the near wake of a bluff body in an axisymmetric confined jet

摘要

An experimental study was performed on an axisymmetric confined jet with a disk, which was installed coaxially to the jet nozzle. Detailed measurements were carried out with a laser Doppler velocimeter, including the various kinds of statistical turbulent quantities such as turbulent intensities, Reynolds shear stresses, skewness and flatness factors as well as the mean velocities in the axial, radial and circumferential directions. The turbulent structure of the near wake flow is discussed for the cases of U{sub}j/U{sub}s ＝ 1.0 and 3.0, where U{sub}j/U{sub}s is the ratio of the jet and en flowing velocities. In addition, the production terms in the transport equation of turbulent kinetic energy are examined based on the experimental results.