Pressure field disturbance

One of the simple ways to achieve active mixing is to induce a pressure field disturbance. Active micromixers relying on this strategy have been reported from different authors [43, 156-159], Deshmuck et al. [156, 157] proposed a T-junction microfluidic chip with an integrated micropump that alternatively drives and stops the flow within the microdevice to create a segmented flow. 

Fig. 16 Mixing by pressure field disturbance (a) Mean fluid velocity along the channel as function of time for in-line inlet and perpendicular inlet. The fluids are pulsed with a simulated 180° phase difference. Contour levels of mass fraction of the fluids in the Y-Z plane are shown, (b) Contour levels In the Y-X plane as a function of time as expressed in the graph in (a). Alternate puffs of fluids are created as result of the pulsation introduced within the fluid stream (Reproduced from [43] by permission of The Royal Society of Chemistry)...

Figure 4.25 Simulated results for periodic pressure field disturbance [50] (a) mean liquid velocity as function of time for the inline inlet (dashed line) and the perpendicular inlet (solid line). Contour levels of the...

To proceed, we again formulate the problem in terms of the disturbance velocity and pressure fields (u, p ), namely,... 

We assume that the velocity and pressure fields are axisymmetric even in the disturbance fields. Although comparison with experiment shows this assumption to be valid for the linear perturbations that are unstable, it eventually breaks down far enough beyond the initial critical point in terms of the cylinder rotation rates. The corresponding linearized [i.e., 0(e)] equations of motion and continuity in dimensional form are... 

Numerical solutions depend strongly on the choice of grid. Using any reservoir simulator, compute the flowfields about stand-alone fractures and shales, say, centered in a large computational box. Do your results satisfy the symmetries and antisymmetries derived here for pressure and normal velocity A single straight shale in an infinite medium has a perfectly antisymmetric disturbance pressure field. Show that this antisymmetry is... 

The supply airflow rate should approximately equal the exhaust flow rate. A minor difference between supply and exhaust flow rates should nor disturb the exhaust, since exhaust systems usually are operated with higher pressure differences than supply systems. If the exhaust flow rate is higher than the supply, it could result in lower efficiency due to lower exhaust flow rates and cross-drafts (see Disturbances). If the exhaust flow rate is lower than the supply flow rate, there may be fewer problems with exhaust efficiency, but this could result in a supply airflow field different from the designed one and thus result in different kinds of disturbances. 

Field-Proof Gun. A special shot gun for taking simultaneously the recoil and pressures at 1 inch and 6 inches from the breech. The velocity and pattern can also be taken at the same time. The gun weighs 50 lbs and is suspended 5 ft below the supports it is fired by means of a pneumatic bulb in order not to disturb the gun. The gpn and support are shown in Fig F2... 

SAFETY PROFILE Human poison by skin contact. Experimental poison by intraperitoneal and subcutaneous routes. An experimental teratogen. Other experimental reproducdve effects. Human systemic effects by ingestion and intravenous routes haUucinadons and distorted percepdons, blood pressure increase, hypermodhty, diarrhea, nausea and vomidng, visual field changes, sleep disturbance. A chemical warfare agent. A combustible liquid. When heated to decomposidon it emits very toxic fumes of SOx and NOx. 

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