In the developing flow region of a plunging jet, the verynear field (i.e. (x-x1)/d1 < 5) is strongly affected by the entrapment process at the impingement. New quantitative results show that, although the distributions of void fraction and mean velocity have smooth shapes, the flow is highly fluctuating and unstable. At a given location in the mixing layer, the probability distribution function...

Abstract. The changes in vortical and turbulent structure in the near field (X/D < 3.0) of jet mixing flow caused by a lobed nozzle were investigated experimentally in the present study. The techniques of planar laser induced fluorescence and particle image velocimetry were used to accomplish flow visualization and velocity field measurements. The experimental results showed that, compared with...

We argue that the narrow line regions of Seyfert galaxies are powered by the transport of energy and momentum by the radio-emitting jets. This implies that the ratio of the radio power to jet energy flux is much smaller than is usually assumed for radio galaxies. This can be partially attributed to the smaller ages (∼ 106 yrs) of Seyferts compared to radio galaxies but one also requires that ei...

The vortical and turbulent structure changes in the near field (X/D<3.0) of the jet mixing flow caused by a lobed nozzle had been investigated experimentally in the present study. The techniques of planar Laser Induced Fluoresce (LIF) and Particle Image Velocimetry (PIV) were used to accomplish the flow visualization and velocity field measurements. The experimental results showed that, compare...

In this study, the coherent structures formed in a round turbulent jet in the vicinity of a free surface are investigated by using proper orthogonal decomposition (POD). The jet issued from a nozzle located at a depth five times the nozzle diameter (d = 10 mm) below and parallel to the free surface. The jet exit velocity was 2.8 m/s and the resulting Reynolds number was 28,000. Instantaneous tw...

in this study, the time-average velocity in the near wake of a two-dimensional notch-back car model that located in the wake of a trailer has been investigated. the present experiments were carried out in an open circuit low-speed wind tunnel made by fara sanjesh saba ltd, in iran and was used to simulate uniform air flow. results show: at the close spacing, time- average velocity profile at th...

Two jets from the Orion (M42) 'proplyds' – kinematics, morphologies and origins. ABSTRACT A spatially unresolved velocity feature, with an approaching radial velocity of ≈ 100 km s −1 with respect to the systemic radial velocity, in a position–velocity array of [O iii] 5007Å line profiles is identified as the kinematical counterpart of a jet from the proplyd LV 5 (158–323) in the core of the Or...

[1] From the physics of radar imaging of ocean surface processes a theoretical model for the radar imaging of an ocean jet was derived. The theoretical model predicts that the jet current structure, sechh, constitutes a determining factor for the radar image. The modeled image intensity depends on the axial velocity, decreasing as x 1 along the jet axis, and is sensitive to the wind direction w...

Very young protostars eject collimated jets of molecular gas. Although the protostars themselves are hidden, some of their properties are revealed through the jet dynamics. We here model velocity shear, precession, pulsation and spray within dense jets injected into less-dense molecular clouds. We investigate the Hammer Jet, for which extreme velocity variations as well as strong ripping and sp...

Direct numerical simulations are performed to investigate the interaction between a stably stratified jet and internal gravity waves from an adjacent shear layer with mild stratification. Results from two simulations are presented: one with the jet located far from the shear layer (far jet) and the other with the shear layer right on top of the jet (near jet). The near jet problem is motivated ...