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This study is to clarify the flow structure of a three-dimensional wall jet discharged tangentially on a flat surface from a circular nozzle. Distributions of the mean velocities and fluctuating velocities in a cross section of a fully-developed flow region were measured by using a single hot-wire probe and cross-wire probes. It is confirmed in any position of the lateral direction that the distributions of the mean velocities U and W in the direction normal to the wall are made similar to each other when they are made dimensionless by the maximum local velocity while the jet height remains almost invariable in the spanwise direction. The direction of the mean flow vector in the inner layer is remained constant while the direction of the mean flow vectors outside the half-value height is coincided with the direction of the jet axis. The distributions of the turbulent statistics in the direction normal to the wall are almost similar to each other outside the half-value height due to the scaling by the maximum local velocity, and on the other hand, the magnitude of the turbulent energy and Reynolds stress in the wall-side region becomes larger at the position farther from the jet axis.

Experimental results of the secondary flow and the turbulence properties of a three-dimensional jet injected from a hole located on the downstream side of a circular cylinder into a uniform flow with a wake or into a quiescent fluid are presented. A secondary flow, such that the cross-sections of the jet are elongated by it to the z-direction, is observed, and deformation of the jet section injected into the uniform flow are considerably larger than those of the jet injected into a quiescent fluid. The fluctuating velocity profiles of the jet injected into a quiescent fluid become a similar form at x/dg 63. In the jet injected into the wake, the turbulence intensity of the jet becomes smaller than those of the wake. It is clarified from the power spectra that the Karman vortex disappears as a result of the interference with the jet.

This study is to clarify the flow structure of a three-dimensional wall jet discharged tangentially on a flat surface from a circular nozzle. Instantaneous pattern of the secondary flow was visualized by tuft-grid methods, and the feature of the large-scale structures existed in the present wall jet was examined. It was revealed from cross-section views that the streamwise vortices with the scale as large as that of the jet height were dominant structures, and that these vortices were moving quasi-periodically toward the outside. And also, a surface flow was visualized with the depth-tuft grid. A dynamic behavior of the streamwise vortices was excellently shown in terms with the tuft image reconstructed at x/d ?? 40 and its two-dimensional spectrum.

An experimental study has been performed on the mean flow properties of the two-dimensional impinging jets on a wedge whose included angle is 90°. The variations in static pressure along the streamwise and transverse directions are large near the vertex of the wedge, and should not be neglected in calculations for these flows. The non-dimensional velocity profiles in the fully-developed-flow region far from the vertex do not coincide with the similarity profile of the two-dimensional wall-jet. Also the trends in the decay of the maximum velocities and in the growth of the half width of the present wall-jets are different to those of the two-dimensional wall jets. The local skin friction coefficients are estimated and compared with the empirical formula proposed by several authors. The logarithmic velocity distribution is examined by using the estimated values of the skin friction coefficients.

An experimental study was performed on the mean flow properties of a two-dimensional impinging jet on a wedge whose included angle is 90°. The variations in static pressure in the streamwise and transverse directions are large near the wedge vertex, and should not be neglected in the calculation of these flows. The non-dimensional velocity profiles in the fully-developed-flow region far from the vertex do not coincide with the similar profile of the two-dimensional wall-jet. Also, the trends in the decay of the maximum velocities and in the growth of the half width of the present wall-jet are different from those of the two-dimensional wall-jet. The local skin friction coefficient is estimated and compared with the empirical formula proposed by several authors. The logarithmic velocity distribution is examined using the estimated skin friction coefficients.

Experimental results of the mean flow properties of a three-dimensional jet injected from a hole located on the downstream side of a circular cylinder into a uniform flow with a wake or into a quiescent fluid are presented. With regard to half widths, Ly and Lz of the jet injected into the quiescent fluid, Lz is slightly larger than Ly. The relative similar profiles of the jets with different Reynolds numbers injected into the uniform flow differ considerably between the vertical direction, y and the horizontal direction, z. The half width L"z in this case is considerably larger than L"y in the upstream region, but two length become nearly equal in the downstream region. The isopleth of the mean velocity is shown to exhibit nonsymmetry and three dimensionality of the flow field.

Turbulence properties and the balance of turbulence energy in a two-dimensional impinging jet on a wedge are investigated. The angles between the wedge surface to the jet axis φ are 30° and 45°. The profiles of u'/Um, v'/Um, q^-2/2U2m in the fully-developed flow region are larger than those of the two-dimensional wall jet, but the profile of w'/Um is almost the same as those, and these profiles are not similar. Each term of the production, the dissipation and the diffusion in the turbulence energy equation is larger than that of the two-dimensional wall jet except for the advection term. The production and the diffusion terms in the case of φ=45° are larger than in the case of φ=30°. The pattern of the isopleths of ^-/U2j in the impinging region differs remarkably with each case of φ=30° and 45°.

Measurements are presented of the mean flow and turbulence properties of threedimensional wall jets injected form a circular nozzle located adjacent to a wall into the turbulent boundary layers, with and without or adverse pressure gradient and a quiescent fluid. The maximum velocities of the wall jets in the boundary layers decrease more slowly toward downstream than in the quiescent fluid, and also these inverse values grow not linearly with the axial distance. The half-widths in the normal and spanwise directions to the wall, Ly and Lz, are considerably small in the wall jets injected into the boundary layers in comparison with those into the quiescent fluid. The variations of the maximum turbulent intensities are discussed in connection with those of twodimensional wall jets, with and without wall flow. The patterns of the isopleths of the mean velocity and turbulent intensity are exhibited.