Fluid flow phenomena in metals processing operations: numerical description of the fluid flow field by an impinging gas jet on a liquid surface

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Effect of nozzle-to-plate spacing on the development of a plane jet impinging on a heated plate

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Numerical study of sediment transport in turbulent two-phase flows around an obstacle

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Numerical and experimental study of a jet in a crossflow for different velocity ratio

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

Parametric analysis of a round jet impingement on a heated plate

International audienceIn this study, the flow and heat transfer characteristics of a round air jet have been experimentally investigated in details using two techniques: Particle Image Velocimetry (PIV) and the Laser Doppler Velocimetry (LDV). The measurement of the mean velocity components are compared, and agree well with the experimental data obtained by Baydar (1999). The distributions of the velocity, turbulence quantities and temperature profiles are analyzed in the main characteristic regions of the jet where the heat transfer occurs. Parametric variations were conducted to produce information about the influences of the Reynolds number (Re = 1000, 2000, 3000), the distance between the pipe exit and the flat impingement plate (hid = 1 and hid = 2) and the temperature of the plane (T-p = 22 degrees C, 54 degrees C, 96 degrees C) on the impinging jet flow field. (C) 2015 Elsevier Inc. All rights reserved

The effect of coflows on a turbulent jet impacting on a plate

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

Bilateral spontaneous thrombosis of the pampiniform plexus; A rare etiology of acute scrotal pain: A case report and review of literature

Introduction: Acute testicular pain is frequent in urology. If torsion of the spermatic cord and orchiepididymites are usual, thrombosis of the pampiniform plexus is a very uncommon clinical entity. We present an unusual case and review the literature to explore potential etiologies and therapeutic strategies. Observation: A rare case of bilateral thrombosis of the pampiniform plexus occurred in a 39 year-old male.The diagnosis was confirmed with doppler sonographie and Computer Tomography. Urethral infection and protein C deficiency were found as associated factors. The treatment was conservative with good result. Conclusions: Anatomical factors are probably responsible for almost exclusive involvement of the left side. However, coagulation abnormalities and retroperitoneal tumors or absence of inferior vena cava must be sought especially in cases of right side or bilateral thrombosis of the pampiniform plexus. The management of pampiniform plexus thrombosis remains non surgical based on symptomatic treatment with good clinical and radiological evolution. Keywords: Thrombosis, Varicocele, Pain, Thrombophili