A new type of out-of-phase oscillatory Turing pattern is found in simulations of a simple two-variable model of a bistable reaction-diffusion system consisting of an autocatalytic activator reacting with a substrate that is replenished by a flow. This class of models can describe pH oscillators or enzymatic reactions. No Hopf instability is necessary for this type of oscillatory Turing pattern.

there are several sources for pressure oscillations in solid propellant rocket motors. oscillatory flow field is one of them. free shear layers in motor flow field cause vortex shedding. end edges of propellant grains and baffle edge in two-segmented motors are samples of such zones. these vortices move from their forming points and strike the field walls. the kinetic energy of vortices change ...

In this work, we consider the feedback control of flows within the vertical Bridgman crystal growth process. We investigate the use of crucible rotation, via feedback control algorithms, in suppressing oscillatory flows in two prototypical vertical Bridgman crystal growth configurations—a laminar flow regime driven by a time-oscillatory furnace disturbance and a time-varying regime driven by st...

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Recently, a novel fluidic actuator using steady suction and oscillatory blowing was developed for active control of high-speed turbulent flows (Arwatz et al. 2008). The suction and oscillatory blowing (SaOB) actuator converts compressed air input into pulsed bistable oscillatory blowing at the actuator outlets. The mechanism for generating bi-stable oscillatory blowing is based upon the Coandă ...

An indicator dilution method for measuring oscillatory flow in a vessel is analyzed in terms of a mixing chamber with a constant volume. For the correct measurement of mean flow, the time constant of detection of the indicator Should be very much shorter than the shortest time constant of the mixing volume. The performance of such a system was examined with a thermal indicator. Although the app...

In the present paper, double-diffusive convection, taking into account Coriolis effects, in a horizontal layer of Brinkman-anisotropic bi-disperse porous medium is analysed. Via linear instability analysis, we find that convection can set through stationary or oscillatory motions and critical Rayleigh numbers for onset secondary flow (steady convection) overstability (oscillatory are determined.

BACKGROUND Exposure to disturbed flow, including oscillatory shear stress, stimulates endothelial cells (ECs) to produce bone morphogenic protein (BMP) 4, which in turn activates inflammation, a critical atherogenic step. BMP activity is regulated by the level of BMP antagonists. Until now it was not known whether shear also regulates the expression of BMP antagonists and whether they play a ro...

The alternating current electroosmotic flow of a non-Newtonian power-law fluid is studied in a circular microchannel. A numerical method is employed to solve the non-linear Poisson-Boltzmann and the momentum equations. The main parameters which affect the flow field are the flow behavior index, the dimensionless zeta potential and the dimensionless frequency. At very low dimensionless frequenci...

Organic nanoparticles of poly(styrene-co-maleimide) or SMI were synthesized in aqueous dispersion with a maximum concentration of 35 wt.% and are favorably applied in industrial coating processes. In order to evaluate the further processability and flow behavior of these nanoparticle dispersions, general rheological characterization under creep, oscillatory and rotational testing was done by ap...