Interfaces stable fluid

Stable Fluid Interfaces Annular Flows and Falling Films... 

In many multiphase microreactor applications, stable fluid interfaces have been particularly important for performing gas-liquid reactions in the annular flow... 

On the other hand stable cavitation (bubbles that oscillate in a regular fashion for many acoustic cycles) induce microstreaming in the surrounding liquid which can also induce stress in any microbiological species present [5]. This type of cavitation may well be important in a range of applications of ultrasound to biotechnology [6]. An important consequence of the fluid micro-convection induced by bubble collapse is a sharp increase in the mass transfer at liquid-solid interfaces. In microbiology there are two zones where this ultrasonic enhancement of mass transfer will be important. The first is at the membrane and/or cellular wall and the second is in the cytosol i. e. the liquid present inside the cell. 

The factors determining the appearance of ordered cell-like motions were first investigated by Sternling and Scriven (S33) who considered the two-dimensional stability of a plane interface separating two immiscible semi-infinite fluid phases with mass transfer occurring between the phases. This system was shown to be unstable for mass transfer in one direction, but stable for transfer in the opposite direction. For an interfacial tension-lowering solute, instability... 

While the fluid dynamics of the actual film-flow process across the disc is daunt-ingly complex, a very approximate interim how model may be based upon Nusselt s treatment of the how of a condensate him. This assumes that the how is stable (i.e., ripple free), that there is no circumferential slip at the disc/liquid surface, and that there is no shear at the gas/liquid interface. The treatment is based... 

Continuous Contactor with Partly Overlapping Channels Solute transfer can occur between immiscible phases each flowing in separate adjacent but displaced microchannels, having only a small conduit in which the fluid interface is stable (partial overlap) [267,268]. 

It must be remembered that in cases when a liquid penetrates into spaces of small cross-section, the important quantity is the adhesion tension y cos 6 or WSL—y. For the distribution of a loose solid powder between two fluid phases, the contact angle is the important quantity, and this must be between 0 and 180° for the powder to be stable at the interface. 

An ideal sample for bottle testing (discussed in the next section) is a stable composite emulsion containing 30% water. When a composite sample is not suitable, as evidenced by a lack of stability, chemical contamination, or low water cut (content), a composite of several wellhead samples must be used. [ Cut refers to the process of determining the BS W (basic sediment and water) content of the oil phase in a sample of produced fluid. Cuts can be taken from the top, middle, or interface of the oil phase.]... 

---