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...

This paper presents an amphibious spherical robot that consists of a sealed upper hemispheroid, two quarter spherical shells, and a plastic circular plate. It has a plastic shelf for carrying themicro-robots, and four actuating units for movement. Each unit is composed of a water-jet propeller and two servomotors, each of which can rotate 90° in the horizontal and vertical directions. The robot...

an experimental study has been performed to investigate the flow physics of an under-expanded axisymmetric supersonic jet exhausting transversely from a flat plate into a subsonic compressible cross flow. the goal was to study the effects of boundary layer thickness ratio (δ/d) and the jet to free stream dynamic pressure ratio (j) on surface pressure. the resulting measurements distinctly show ...

in this study, the effect of suction and the parameters such as suction amplitude, suction coefficient and suction jet length on naca0012 was evaluated. the turbulence employed model was the rsm model. suction jet is located in 10% of the chord length. the range of suction jet entrance velocity was selected from 0.1 to 0.5 of freestream velocity. the maximum increase in lift to drag ratio was s...

one of the world's major mineral dust source regions lies along the border between iran and afghanistan. in this studyit is hypothesized that a low-level jet may play in role in generating the intensity of this source region. the presence of alow-level jet east of the seistan mountains is documented here for the first time. the jet exists mainly from may toseptember and has a core at 850 mb. ma...

A midlatitude mesoscale convective complex (MCC), which occurred over the central United States on 23– 24 June 1985, was simulated using the Regional Atmospheric Modeling System (RAMS). The multiply nestedgrid simulation agreed reasonably well with surface, upper-air, and satellite observations and ground-based radar plots. The simulated MCC had a typical structure consisting of a leading line ...