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We demonstrate a method to achieve an extremely wide and flexible external control of the group velocity of signals as they propagate along an optical fibre. This control is achieved by means of the gain and loss mechanisms of stimulated Brillouin scatteri ...
In this study the scour mechanism and the effect of some of the important parameters such as jet velocities, impinging jet distance from the upstream wall and tailwater depth on the longitudinal scour profile due to 3d simoultaneous wall and impinging jet ...
The dissipation of energy of flood discharges from water releasing structures of dams is often done by plunging jets diffusing in water and impacting on the riverbed downstream. The construction of expensive concrete structures for energy dissipation can b ...
High-velocity plunging jets, issuing from ood release structures of dams, may result in scouring of the rocky riverbed and even endanger the foundation of the dams. Assessment of the scour extent is essential to ensure the safety of the dam and appurtenant ...
The fluctuating behaviour of a Sulzer Metco F4 DC plasma gun has been investigated. The time dependencies of the arc voltage and current and of the optical emission of the plasma jet have been measured. An optical fibre inside the gun allows direct measure ...
The safety of dams is very often endangered by the formation of scour near the foundation as a result of high-velocity jet impact. These jets issue from appurtenant structures such as spillways and may impact in the immediate vicinity of the dam toe. The p ...
Similarly to neutral fluids, plasmas often exhibit turbulent behavior. Turbulence in plasmas is usually more complex than in neutral fluids due to long range interactions via electric and magnetic fields, and kinetic effects. It gives rise to many interest ...
The impingement of high-velocity water jets on unlined plunge pools causes scour on the rock foundations. The scour process is the result of complex physical phenomena that happen consecutively. Turbulence and dynamic pressures play a major role, especiall ...
Rock scour occurring near dam foundations due to high-velocity jets of spillways impinging into the plunge pool is a major concern regarding dam safety. Scour in fractured rock resulting from high-velocity jet impact is a complex phenomenon, which involves ...
The radial propagation of plasma blobs and possibilities of influencing it are investigated in the TORPEX toroidal experiment [Fasoli et al., Phys. Plasmas 13, 055902 (2006)]. The effect of changing the connection length and the neutral background pressure ...