Numerical Study of Turbulent Axisymmetric Jets Impinging on a Flat Plate and Flowing Into an Axisymmetric Cavity

Abstract

A numerical study is made of the characteristics of turbulent submerged axisymmetric incompressible jets impinging on a flat plate and flowing into an axisymmetric cavity. The purpose of the study is to obtain a better understanding of the behavior of a fluid jet used to cut solid materials. In the computations a hybrid finite difference method is used to solve the full Navier-Stokes equations for an incompressible submerged jet with the k ∼ ε turbulence model. All computed results are compared with experimental data reported in the literature. For the case of the jet impinging on a flat plate, the computations are made for nozzle-to-plate distances ranging from 2 to 40 nozzle diameters. For the jet flowing into an axisymmetric cavity, computations are made for cavity depths ranging from 0 to 60 nozzle diameters. The use of the k ∼ ε turbulence model results in good predictions of the velocity, pressure, and skin friction distributions. The near-wall models for the kinetic energy and turbulent shear stress give good predictions of the skin friction coefficients.