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International audienceThe study examines the dynamic and the turbulent behavior of a plane jet impinging normally on a flat target plate in a flow at rest or in a coflow stream. First, numerical and experimental investigations of the characteristics of a turbulent plane jet impinging on a flat surface in still air are depicted. The measurements are conducted using Particle Image Velocimetry (PIV). A comparison has been carried out between numerical results of three turbulence closure models (k-epsilon standard model, RNG k-epsilon model and a second-order model RSM) and experimental data. It has been found that the second order turbulence model (RSM) reasonably predicts the mean flow properties of the flow field. Next, a numerical study of the flow field of an impinging jet in a coflow stream is conducted. The study of the jet in a no-directed coflow stream shows the presence of a phenomenon of recirculation near the flat plate. In addition, the study focuses on the influence of the coflow velocity ratio on the behavior of an impinging jet and the influence of the directed co-flow on various physical parameters such as the mean and the turbulent quantities. The results clearly show that the coflow stream imposed noticeable restrictions on the spreading of the impinging jet and decreases considerably the entrainment of air jet. (C) 2016 Elsevier Inc. All rights reserved

International audienceThis paper deals with a flow generated by the interaction between a circular jet and a crossflow for different velocity ratios (R = v(0)/u(infinity)). This particular side of this study is of extremely high interest as it allows a better understanding of the mixing process of different interacting flows. This work presents experimental results obtained by means of the particle image velocimetry technique to track the evolution of the jet among the environment flow. Results showed the dependence of the emerging jet flow structure on its ratio velocity. A three-dimensional numerical model with a second-order turbulent model (RSM) and a non-uniform grid system is used to examine the behavior of the emerging jet in the crossflow. The comparison of the numerical and experimental results gives satisfactory agreement

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