Characteristics of a thin curved wall jet and an annular jet guided by a spherical surface are investigated. Main purpose of the present study is to evaluate the influence of large curvature surface on the development of an annular jet. Interaction of a thin annular jet guided by a half-spherical surface and a coaxial round jet ejected from the center of the half-sphere is also investigated. Using a three beam, two component-polarization Laser Doppler Velocimetry, mean velocity, turbulent intensity, Reynolds shear stress, potential core length and energy spectrum are obtained for five velocity ratios.
Results of the axial mean velocity along the centerline decays at a rate of $(X-X_O)^{-0.68}$ for λ = ∞, $(X-X_O)^{-0.86}$ for λ = 1.517, $(X-X_O)^{-1}$ for λ = 0.961 and $(X-X_O)^{-1.12}$ for λ = 0.494.
In case of high mean-velocity rations, the potential core length is inversely proportional to the velocity ratios. In the annular separation bubble zone, owing to the collision between the jets, the turbulent intensity and Reynolds shear stress becomes very high.
