Measurement of Interfacial Parameters of Single Taylor Bubbles Rising in Closed Vertical and Slightly Inclined Tubes Using Ultrasonic and Visualization Techniques.

Quantifying the influence of conduit inclination on Taylor Bubble behaviour in basaltic magmas.

“…To measure the thickness of the falling film, λ, in inclined tubes, the bubble width was added to the width of the lower film thickness (i.e., in an inclined tube the bubble ascends closer to the upper tube wall) then the total was subtracted from the internal diameter (Figure 1). Falling film thickness was measured in vertical tubes by subtracting bubble width from internal tube diameter then halving the resulting value because falling films present symmetry in all directions around the bubble when the condition of the surrounding tube is vertical (de Azevedo et al, 2015).…”

“…Within tubes of vertical geometry bubble morphology is axisymmetric and the Taylor bubble ascends the pipe centre (Zukoski, 1966) and consistently with previous works (Table 1), the shape of the nose and body remain qualitatively the same for both diameters in vertical tubes, i.e., when θ = 0, independent of bubble length. In Taylor bubbles the ratio of bubble to tube diameter is > 0.6, so tube diameter is the controlling length governing nose shape (de Azevedo et al, 2015), and as liquid viscosity increases, the shape of the bubble nose becomes blunter and velocity decreases. These observations also apply to inclined tubes in addition to a gradual change in bubble shape that is observed with increasing inclination.…”