Cloud cavitation shows an unsteady periodic tendency under a certain flow condition. In a cavitating water jet flow with cavitation clouds, the cavities or the clouds produce high impact at their collapse. In order to make clear a mechanism of the periodic cavity behavior, we experimentally examine the behavior in a transparent cylindrical convergent-divergent nozzle using a high-speed video ca...

M87 has been recently shown to be a TeV source which is likely to be variable. Based on this, and on contemporaneous optical and X-ray monitoring, we argue that the source of the TeV emission is the core of M87 and not one of two jet knots (HST-1 and A) with X-ray brightness comparable to that of the core. We model the TeV emission in the core as inverse Compton (IC) emission from the base of t...

A model of the interaction of the noise from a spreading subsonic jet with a 4 panel assembly is studied numerically in two dimensions. The e ect of forward motion of the jet is accounted for by considering a uniform ow eld superimposed on a mean jet exit pro le. The jet is initially excited by a pulse-like source inserted into the ow eld. The pulse triggers instabilities associated with the in...

Abstract The intensity and location of boreal summer extratropical intraseasonal oscillations along the subtropical westerly jet (EISO-SJ) are crucial in triggering distributing extreme events over Eurasia. Based on numerical experiments, this study distinguishes orographic mechanical surface thermal forcing Tibetan–Iranian Plateau (i.e. TIP-MF TIP-TF) EISO-SJ. primarily modulates amplitude EIS...

Predictive and real-time inference capability for the upstream separatrix electron density, $n_\text{e, sep}$, is essential design control of core-edge integrated plasma scenarios. In this study, both supervised semi-supervised machine learning algorithms are explored to establish direct mapping as well indirect compressed representation pedestal profiles predictions $n_{\text{e, sep}}$. Based ...

The radiation of sound from a perfectly expanded Mach 2.5 cold supersonic jet of 25.4 mm exit diameter flowing through a partially open rigid-walled duct with an upstream i-deflector has been studied experimentally. In the experiments, the nozzle is mounted vertically, with the nozzle exit plane at a height of 73 jet diameters above ground level. Relative to the nozzle exit plane (NEP), the loc...

Schlieren flow visualizations of transverse oscillations of jets submitted to an acoustic perturbation are analyzed in this paper. The aim is to estimate the shape and the position of the median line of the jet. Two methods for image processing are proposed, based on complementary approaches : inter image and intra image analysis. Synthesized images of an oscillating jet are used to validate ea...

The flow and acoustic fields of jets at a Mach number 3.1 impinging on plate the jet nozzle exit, where is diameter, have been investigated using highly resolved large-eddy simulations. perforated with hole diameter , or . full-plate free-jet cases also considered. pressure levels are highest for non-perforated decrease as increases. Compared free jet, they higher by about 5 dB full plate, 4 3 ...

The upstream-propagating waves of feedback loops in under-expanded impinging jets are investigated through several typical flow conditions. Schlieren image capturing and far-field acoustic measurement applied to the jet. structures related discrete tones extracted dynamic mode decomposition (DMD), standing formed by resonance identified from normalized amplitude fields chosen DMD modes. Spatial...