非圧縮性流体に関する湾曲した乱流平面噴流の解析

抄録

Although curved jets have been treated analytically by several authors from the viewpoint of similar solutions, a jet along a circular arc often appearing in practical applications seems to remain unsolved. The purpose of this paper is to solve such a non-similar flow field of an incompressible turbulent plane jet. Applying the approximation of boundary layer type, an integrated form of the vorticity equation, referred to an orthogonal curvilinear coordinate system, retains only the shear stress terms, as represented by the SAWYER'S expression.
The small perturbation method, used by TANI for the first time to the boundary layer problem along a curved wall, is extended to solve a laminar curved jet by the present authors in the preceding paper. In this method, the perturbation parameter, which is the small ratio of the jet width to the radius of curvature of the zerostreamline, is expressed by a power function of the stream-wise coordinate, providing the desired solution in the case of constant pressure across the jet.
Non-similar velocity distributions are calculated along several planes normal to the zero-streamline, and it is found, as observed by SAWYER, that the total entrainment rate of the jet is strictly identical to and the total jet spread rate is almost identical to those of a symmetrical jet, and that the velocity profiles of the curved jet are nearly symmetrical.