We study the initial value problem for the 3-D Euler equation when the fluid is inviscid and incompressible, and flows with axisymmetry and without swirl. On the initial vorticity ω0, we assumed that ω0/r belongs to L(logL(R3))α with α > 1/2, where r is the distance to an axis of symmetry. To prove the existence of weak global solutions, we prove first a new a priori estimate for the solution. ...

Single-phase heat transfer and pressure drop tests were conducted in a tube with two types of twisted tapes. Each tape had exactly similar physical parameters made the same material except that each an opposite twist resulted clockwise anticlockwise flow swirl, i.e., left turn right turn, respectively. type ratio 4 5.5 on 180° twist. The tapes tested tube-in-tube exchanger having 2 m length. in...

Mitochondrial dysfunction and reactive oxygen species have been implicated in the aging process as well as a wide range of hereditary and age-related diseases. Identifying primary events that result from acute oxidative stress may provide targets for therapeutic interventions that preclude aging. By using electron microscopy, we have discovered a striking initial pattern of degeneration of the ...

Controlling the flame shape and its liftoff height is one of main issues for oxy-flames to limit heat transfer solid components injector. An extensive experimental study carried out analyze effects co- counter-swirl on flow patterns non-premixed stabilized above a coaxial injector when both inner fuel annular oxidizer streams are swirled. A swirl level greater than 0.6 in stream shown yield com...

Abstract Boundary layer ingestion (BLI) offers potential reductions in fuel burn and emissions. The propulsive fuselage concept features an aft fan that ingests the 360 deg boundary layer. A critical condition for this configuration occurs when a sideslip angle arises between aircraft longitudinal axis freestream velocity. flow combination with airframe generates inlet distortion depends on dir...

The vortex/swirl flowmeters are meant to measure the flowrate based on the measurement of the flow frequency. Due to the frequency-dependent computation of the flowrate, noflow pulsation causes a false positive, i.e., it indicates certain amount of flowrate when actually there is no flow. This happens when for example, the valves of the flow pipe are closed causing no flow, but some pumps are w...

The interaction of a droplet with swirling airstream is investigated experimentally using shadowgraphy and particle image velocimetry techniques. In swirl flow, the experiences oppose-flow, cross-flow co-flow conditions depending on its ejection location, velocity strength, which results in distinct morphologies as compared straight airflow situation. We observe new breakup phenomenon, termed ‘...

The egg of the frog Xenopus is cylindrically symmetrical about its animal-vegetal axis before fertilization. Midway through the first cell cycle, the yolky subcortical cytoplasm rotates 30 degrees relative to the cortex and plasma membrane, usually toward the side of the sperm entry point. Dorsal embryonic structures always develop on the side away from which the cytoplasm moves. Details of the...