A three-dimensional vortex element method is developed to simulate the flow field of an incompressible transverse jet at high Reynolds number — in particular, to explore the response of large-scale vortical structures in the jet to actuation. Vorticity produced in the channel wall boundary layer interacts with the jet flow at the nozzle exit, producing both axial and azimuthal perturbations to ...

AIM To examine the cardiovascular effects of an intravenous bolus of morphine, 100 microg/kg, in 17 ventilated preterm infants. METHODS Heart rate and blood pressure were monitored. Right ventricular output, superior vena caval flow, and the width of the ductus arteriosus were measured by Doppler echocardiography 10 and 60 minutes after the morphine injection, and the values compared with bas...

A plane subsonic jet was subjected to periodic oscillations in the near nozzle region by a twin vane system. During excitation, the jet was found to spread significantly and entrain mass much more than its steady counterpart. Time averaged static pressure measured in the flow field with a disc probe exhibited prominent well defined suction regions different from that of a steady jet.

Introduction Jet pumps are static components that can be used in closed-loop, traveling wave thermoacoustic devices to suppress a time-averaged mass flux (Gedeon streaming) that can exist [2]. The minimization of convective heat transport caused by this mass flux is of vital importance due to the detrimental effect it has on the device’s efficiency. Jet pumps have an asymmetric shape, resulting...

We present a systematic study of capillary filling for multi-phase flows by using mesoscopic lattice Boltzmann models describing a diffusive interface moving at a given contact angle with respect to the walls. We compare the numerical results at changing the density ratio between liquid and gas phases, δρ/ρ and the ratio, δξ/H , between the typical size of the capillary, H , and the interface w...

We studied surface adherence and its effects on color Doppler jet areas and color encoding in an in vitro model with a noncompliant receiving chamber into which a steady flow jet was directed parallel to either a straight or a curved surface adjacent to and 4 mm away from the inflow orifice (1.50 mm2) with the control condition being a free jet matched for flow rates and driving pressures. Jets...

Passiflora contracta Vitta (Passifloraceae) is an endemic species of the Atlantic Rainforest, one of the most species-rich ecoregions in the world, although extremely endangered. We have developed an enriched microsatellite library in order to fine-scale studies of the genetic structure of P. contracta. Twelve pairs of microsatellite primers were designed, and seven loci were successfully ampli...

Flip buckets are terminal spillway elements, generating free jets for energy dissipation. Deflectors are an alternative to flip buckets with constructional ease yet of similar hydraulic features. A first experimental study published at the 33 IAHR Congress, Vancouver, investigated deflectorgenerated jets in terms of their air concentration characteristics. For jet impact onto a movable bed, the...

Recent studies of impinging jet flows have shown that momentum and heat transfer can be significantly improved if the jet flow is pulsed (Zumbrunnen, 1996). Moreover, when the jet holes are elliptical, jet free surfaces are formed into a helical structure. These helical structures in a jet flow can be readily observed by squeezing a garden hose into an elliptic shape. Upon pulsating the jet flo...